From btremblay at me.com  Wed Sep  4 06:22:14 2024
From: btremblay at me.com (Benjamin Tremblay)
Date: Wed, 4 Sep 2024 00:22:14 -0400
Subject: [sdiy] Beyond bending: clock sweeping Korg MSM6235 etc
Message-ID: <89CAC971-6EB1-4CEC-9D89-48D3143F9260@me.com>

I?m too tired to write coherent thoughts but I will clarify asap.

The Korg drum voice chips are clocked at 250khz so divided down from a 4mhz clock using a binary counter. 

First of all, you can use the other outputs to run the drum voice chips at powers of 2 higher speeds which is neat.

I remembered in college I got my DDM-110 super duper drums to sweep playback pitch using a knob or control voltage. I could sweep it from 2x speed down to low grinding crunchy oblivion. 

How did I do it? 

I?m not totally sure how it works, but if I disconnect the MSM6235  clock inputs from the D output of the binary counter, reconnect these to the C output (500khz)  and run a capacitor (less than 10nf) from the binary counter D output to a 250K potentiometer and the back into the clock input pin on the counter?.
(I think that makes sense) you can sweep from 500khz way down. Something about any output pin on the counter feeding back into the clock input via an rc circuit seems to slow the clock without slowing the speed of the main CPU. 
If I connect the drum sound chips to the A output of the binary counter (2mhz) and connect my ?sweep? pin to output D it?s a very wide range but the audio playback sounds distorted like the clock is a staircase wave. 
Anyway I thought I would write this down and share with anyone interested in these chips used in the MR-16 etc. I will try this with the PSS-50.
Ben

Benjamin Tremblay
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From btremblay at me.com  Wed Sep  4 16:24:58 2024
From: btremblay at me.com (Benjamin Tremblay)
Date: Wed, 4 Sep 2024 10:24:58 -0400
Subject: [sdiy] Beyond bending: clock sweeping Korg MSM6235 etc
In-Reply-To: <89CAC971-6EB1-4CEC-9D89-48D3143F9260@me.com>
References: <89CAC971-6EB1-4CEC-9D89-48D3143F9260@me.com>
Message-ID: <AD2682E8-44AA-4AC3-B5AE-C18A47ED28AC@me.com>

My plan here is to add MIDI triggering to the Korg DDM-110 and -220, and MIDI pitch bend. 
I will use 4066 switches for the drum keys and to change the routing of the drum voice clocks so that a neutral pitch bend position produces a perfect 250khz clock signal. 

If the switch matrix was bigger I would use a crosspoint switch. I may be able to simply poke values into the latches used in the control board but the 4066 seems like a safe way to isolate old and new logic. 

Interesting compendium of early 80s consumer-grade  drum machine voice chips here. I bet much of this would work with some of the Casio things... I have a Casio HT-700 so could try (or rip out the drum chip for fun).
https://acreil.wordpress.com/2017/10/18/casio-and-korg-drum-ics/?
Casio and Korg drum ICs
acreil.wordpress.com


?

?



> On Sep 4, 2024, at 12:22?AM, Benjamin Tremblay via Synth-diy <synth-diy at synth-diy.org> wrote:
> 
> I?m too tired to write coherent thoughts but I will clarify asap.
> 
> The Korg drum voice chips are clocked at 250khz so divided down from a 4mhz clock using a binary counter. 
> 
> First of all, you can use the other outputs to run the drum voice chips at powers of 2 higher speeds which is neat.
> 
> I remembered in college I got my DDM-110 super duper drums to sweep playback pitch using a knob or control voltage. I could sweep it from 2x speed down to low grinding crunchy oblivion. 
> 
> How did I do it? 
> 
> I?m not totally sure how it works, but if I disconnect the MSM6235  clock inputs from the D output of the binary counter, reconnect these to the C output (500khz)  and run a capacitor (less than 10nf) from the binary counter D output to a 250K potentiometer and the back into the clock input pin on the counter?.
> (I think that makes sense) you can sweep from 500khz way down. Something about any output pin on the counter feeding back into the clock input via an rc circuit seems to slow the clock without slowing the speed of the main CPU. 
> If I connect the drum sound chips to the A output of the binary counter (2mhz) and connect my ?sweep? pin to output D it?s a very wide range but the audio playback sounds distorted like the clock is a staircase wave. 
> Anyway I thought I would write this down and share with anyone interested in these chips used in the MR-16 etc. I will try this with the PSS-50.
> Ben
> 
> Benjamin Tremblay
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
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From james at ticalun.net  Thu Sep  5 18:55:46 2024
From: james at ticalun.net (James Coplin)
Date: Thu, 05 Sep 2024 11:55:46 -0500
Subject: [sdiy] Covers / shroud for unused header pins?
Message-ID: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>

I was wondering if anyone can point at some product or tell me how you would handle the problem of exposed unused pins on headers?

Yesterday, I burned out a board when an exposed piece of connector happened to touch some exposed pins while opening and closing the case. I've looked around for some sort of a cap or cover so the pins are exposed to shorting and I'm surprised I'm not finding anything? Maybe I just don't know what they are called.

Does anyone have a solution to these exposed pins? I might just 3d print something but that seems excessive from a fiddly time perspective.

James R Coplin


From jason at tribbeck.com  Thu Sep  5 19:19:29 2024
From: jason at tribbeck.com (Jason Tribbeck)
Date: Thu, 5 Sep 2024 18:19:29 +0100
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
Message-ID: <CAL3=FbbGzs5VqNNj3F3COg2LEQs7jH89Yr3mnyMRP9p__QX3+g@mail.gmail.com>

I'd use an unpopulated IDC header...

On Thu, 5 Sept 2024, 17:55 James Coplin, <james at ticalun.net> wrote:

> I was wondering if anyone can point at some product or tell me how you
> would handle the problem of exposed unused pins on headers?
>
> Yesterday, I burned out a board when an exposed piece of connector
> happened to touch some exposed pins while opening and closing the case.
> I've looked around for some sort of a cap or cover so the pins are exposed
> to shorting and I'm surprised I'm not finding anything? Maybe I just don't
> know what they are called.
>
> Does anyone have a solution to these exposed pins? I might just 3d print
> something but that seems excessive from a fiddly time perspective.
>
> James R Coplin
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>
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From james at ticalun.net  Thu Sep  5 20:05:01 2024
From: james at ticalun.net (James Coplin)
Date: Thu, 05 Sep 2024 13:05:01 -0500
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <CAL3=FbbGzs5VqNNj3F3COg2LEQs7jH89Yr3mnyMRP9p__QX3+g@mail.gmail.com>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <CAL3=FbbGzs5VqNNj3F3COg2LEQs7jH89Yr3mnyMRP9p__QX3+g@mail.gmail.com>
Message-ID: <4750e64e-1dd9-4bae-800f-ffaf3a585ab2@ticalun.net>

The unpopulated doesn't have enough grab. I suppose I could put a couple terminals in there.

James

?Get BlueMail for Android ?

On Sep 5, 2024, 12:19?PM, at 12:19?PM, Jason Tribbeck <jason at tribbeck.com> wrote:
>I'd use an unpopulated IDC header...
>
>On Thu, 5 Sept 2024, 17:55 James Coplin, <james at ticalun.net> wrote:
>
>> I was wondering if anyone can point at some product or tell me how
>you
>> would handle the problem of exposed unused pins on headers?
>>
>> Yesterday, I burned out a board when an exposed piece of connector
>> happened to touch some exposed pins while opening and closing the
>case.
>> I've looked around for some sort of a cap or cover so the pins are
>exposed
>> to shorting and I'm surprised I'm not finding anything? Maybe I just
>don't
>> know what they are called.
>>
>> Does anyone have a solution to these exposed pins? I might just 3d
>print
>> something but that seems excessive from a fiddly time perspective.
>>
>> James R Coplin
>>
>> ________________________________________________________
>> This is the Synth-diy mailing list
>> Submit email to: Synth-diy at synth-diy.org
>> View archive at: https://synth-diy.org/pipermail/synth-diy/
>> Check your settings at:
>https://synth-diy.org/mailman/listinfo/synth-diy
>> Selling or trading? Use marketplace at synth-diy.org
>>



From music at atypical.net  Thu Sep  5 20:14:12 2024
From: music at atypical.net (music at atypical.net)
Date: Thu, 5 Sep 2024 14:14:12 -0400
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <4750e64e-1dd9-4bae-800f-ffaf3a585ab2@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <CAL3=FbbGzs5VqNNj3F3COg2LEQs7jH89Yr3mnyMRP9p__QX3+g@mail.gmail.com>
 <4750e64e-1dd9-4bae-800f-ffaf3a585ab2@ticalun.net>
Message-ID: <1075a1c2-63df-4e08-b829-2163da12f39a@atypical.net>

Attach an unpopulated female header to a piece of ribbon cable, then cut 
the ribbon cable flush with the connector?

On 2024-09-05 14:05, James Coplin wrote:
> The unpopulated doesn't have enough grab. I suppose I could put a couple terminals in there.
>
> James
>
> ?Get BlueMail for Android ?
>
> On Sep 5, 2024, 12:19?PM, at 12:19?PM, Jason Tribbeck <jason at tribbeck.com> wrote:
>> I'd use an unpopulated IDC header...
>>
>> On Thu, 5 Sept 2024, 17:55 James Coplin, <james at ticalun.net> wrote:
>>
>>> I was wondering if anyone can point at some product or tell me how
>> you
>>> would handle the problem of exposed unused pins on headers?
>>>
>>> Yesterday, I burned out a board when an exposed piece of connector
>>> happened to touch some exposed pins while opening and closing the
>> case.
>>> I've looked around for some sort of a cap or cover so the pins are
>> exposed
>>> to shorting and I'm surprised I'm not finding anything? Maybe I just
>> don't
>>> know what they are called.
>>>
>>> Does anyone have a solution to these exposed pins? I might just 3d
>> print
>>> something but that seems excessive from a fiddly time perspective.
>>>
>>> James R Coplin
>>>
>>> ________________________________________________________
>>> This is the Synth-diy mailing list
>>> Submit email to: Synth-diy at synth-diy.org
>>> View archive at: https://synth-diy.org/pipermail/synth-diy/
>>> Check your settings at:
>> https://synth-diy.org/mailman/listinfo/synth-diy
>>> Selling or trading? Use marketplace at synth-diy.org
>>>
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org

From cheater00social at gmail.com  Thu Sep  5 20:36:28 2024
From: cheater00social at gmail.com (cheater cheater)
Date: Thu, 5 Sep 2024 20:36:28 +0200
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
Message-ID: <CAGn5V--1jzUOTpy=_t79cymgsmTtH11Fs-vmsYM30ASApt+KEQ@mail.gmail.com>

strip of corrugated cardboard

On Thu, Sep 5, 2024 at 7:00?PM James Coplin <james at ticalun.net> wrote:
>
> I was wondering if anyone can point at some product or tell me how you would handle the problem of exposed unused pins on headers?
>
> Yesterday, I burned out a board when an exposed piece of connector happened to touch some exposed pins while opening and closing the case. I've looked around for some sort of a cap or cover so the pins are exposed to shorting and I'm surprised I'm not finding anything? Maybe I just don't know what they are called.
>
> Does anyone have a solution to these exposed pins? I might just 3d print something but that seems excessive from a fiddly time perspective.
>
> James R Coplin
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org


From dh at atoav.com  Thu Sep  5 21:11:41 2024
From: dh at atoav.com (David Huss)
Date: Thu, 05 Sep 2024 19:11:41 +0000
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
Message-ID: <74794BBA-3B46-472C-A25D-F133C4314BC3@atoav.com>

Can't point you to a specific product, but I have seen a rubber (?) Cover on smaller pitch JTAG headers e.g. on the Daisy Seed.

What about a neatly cut piece of insulating tape?



On September 5, 2024 4:55:46 PM UTC, James Coplin <james at ticalun.net> wrote:
>I was wondering if anyone can point at some product or tell me how you would handle the problem of exposed unused pins on headers?
>
>Yesterday, I burned out a board when an exposed piece of connector happened to touch some exposed pins while opening and closing the case. I've looked around for some sort of a cap or cover so the pins are exposed to shorting and I'm surprised I'm not finding anything? Maybe I just don't know what they are called.
>
>Does anyone have a solution to these exposed pins? I might just 3d print something but that seems excessive from a fiddly time perspective.
>
>James R Coplin
>
>________________________________________________________
>This is the Synth-diy mailing list
>Submit email to: Synth-diy at synth-diy.org
>View archive at: https://synth-diy.org/pipermail/synth-diy/
>Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
>Selling or trading? Use marketplace at synth-diy.org


From synthimuse at gmail.com  Thu Sep  5 21:27:58 2024
From: synthimuse at gmail.com (The SynthiMuse)
Date: Thu, 5 Sep 2024 20:27:58 +0100
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
Message-ID: <CAJ-kJoCQh4qGLzx3c_kAf0RRYhAtb6KLMjY2LBePo8FCgPR6ug@mail.gmail.com>

If it's just 1 or 2 pins, you could strip some appropriately-sized wire and
slide a length of insulation on to the pins, then melt a little spot of the
insulation so it bonds to the pin.

Alternatively,  if you have some heatshrink tubing, that would be the ideal
solution.
Gerry

On Thu, 5 Sept 2024, 18:00 James Coplin, <james at ticalun.net> wrote:

> I was wondering if anyone can point at some product or tell me how you
> would handle the problem of exposed unused pins on headers?
>
> Yesterday, I burned out a board when an exposed piece of connector
> happened to touch some exposed pins while opening and closing the case.
> I've looked around for some sort of a cap or cover so the pins are exposed
> to shorting and I'm surprised I'm not finding anything? Maybe I just don't
> know what they are called.
>
> Does anyone have a solution to these exposed pins? I might just 3d print
> something but that seems excessive from a fiddly time perspective.
>
> James R Coplin
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>
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From jdec at mindspring.com  Thu Sep  5 21:45:55 2024
From: jdec at mindspring.com (BrightBoy)
Date: Thu, 05 Sep 2024 19:45:55 +0000
Subject: [sdiy] Covers / shroud for unused header pins?
Message-ID: <e5ed822d-7441-8ba1-25fb-08437119e0e1@mindspring.com>

It's like you need header shunts without the actual shunt between the two pin sockets.

J. Dec

-----Original Message-----
From: James Coplin <james at ticalun.net>
Sent: Sep 5, 2024 1:08 PM
To: synth-diy mailing list <synth-diy at synth-diy.org>
Subject: [sdiy] Covers / shroud for unused header pins?

I was wondering if anyone can point at some product or tell me how you would handle the problem of exposed unused pins on headers?

Yesterday, I burned out a board when an exposed piece of connector happened to touch some exposed pins while opening and closing the case. I've looked around for some sort of a cap or cover so the pins are exposed to shorting and I'm surprised I'm not finding anything? Maybe I just don't know what they are called.

Does anyone have a solution to these exposed pins? I might just 3d print something but that seems excessive from a fiddly time perspective.

James R Coplin

________________________________________________________
This is the Synth-diy mailing list
Submit email to: Synth-diy at synth-diy.org
View archive at: https://synth-diy.org/pipermail/synth-diy/
Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
Selling or trading? Use marketplace at synth-diy.org




From obl64 at ix.netcom.com  Thu Sep  5 21:46:14 2024
From: obl64 at ix.netcom.com (Oren Leavitt)
Date: Thu, 5 Sep 2024 14:46:14 -0500
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
Message-ID: <f14c1de2-59cb-4810-be8e-ea021e6ecc33@ix.netcom.com>

Wire insulation strippings work great for this, or for insulating short 
jumpers. I save those when stripping hook up wire.

22 to 18 gauge insulation fits snugly over most standard header pins.

- Oren


On 9/5/24 11:55 AM, James Coplin wrote:
> I was wondering if anyone can point at some product or tell me how you would handle the problem of exposed unused pins on headers?
>
> Yesterday, I burned out a board when an exposed piece of connector happened to touch some exposed pins while opening and closing the case. I've looked around for some sort of a cap or cover so the pins are exposed to shorting and I'm surprised I'm not finding anything? Maybe I just don't know what they are called.
>
> Does anyone have a solution to these exposed pins? I might just 3d print something but that seems excessive from a fiddly time perspective.
>
> James R Coplin
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org

From fanwander at mnet-online.de  Thu Sep  5 22:47:13 2024
From: fanwander at mnet-online.de (Florian Anwander)
Date: Thu, 5 Sep 2024 22:47:13 +0200
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <4750e64e-1dd9-4bae-800f-ffaf3a585ab2@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <CAL3=FbbGzs5VqNNj3F3COg2LEQs7jH89Yr3mnyMRP9p__QX3+g@mail.gmail.com>
 <4750e64e-1dd9-4bae-800f-ffaf3a585ab2@ticalun.net>
Message-ID: <60d6384f-659e-488b-b9a9-f6948fd93c99@mnet-online.de>

Why shouldn't they? A header socker like 
https://de.rs-online.com/web/p/idc-steckverbinder/6257369 doesn't rely 
mechanically in any way on beeing connected to a wire.

I'd advise definitely against isolating hose or shrink tube, because 
there will come the situation, when you want to access the header pin 
(usually it will be a test point).

Am 05.09.24 um 20:05 schrieb James Coplin:
> The unpopulated doesn't have enough grab. I suppose I could put a couple terminals in there.
>> I'd use an unpopulated IDC header...
>>> I was wondering if anyone can point at some product or tell me how you
>>> would handle the problem of exposed unused pins on headers?
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From james at ticalun.net  Fri Sep  6 00:28:19 2024
From: james at ticalun.net (James Coplin)
Date: Thu, 05 Sep 2024 17:28:19 -0500
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <60d6384f-659e-488b-b9a9-f6948fd93c99@mnet-online.de>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <CAL3=FbbGzs5VqNNj3F3COg2LEQs7jH89Yr3mnyMRP9p__QX3+g@mail.gmail.com>
 <4750e64e-1dd9-4bae-800f-ffaf3a585ab2@ticalun.net>
 <60d6384f-659e-488b-b9a9-f6948fd93c99@mnet-online.de>
Message-ID: <b1f1152a-6389-4492-927f-cdd3701aaf24@ticalun.net>

Ah, I was thinking the type you load the termini also into after crimping wire, not a ribbon type. 

James

?Get BlueMail for Android ?

On Sep 5, 2024, 3:47?PM, at 3:47?PM, Florian Anwander <fanwander at mnet-online.de> wrote:
>Why shouldn't they? A header socker like 
>https://de.rs-online.com/web/p/idc-steckverbinder/6257369 doesn't rely 
>mechanically in any way on beeing connected to a wire.
>
>I'd advise definitely against isolating hose or shrink tube, because 
>there will come the situation, when you want to access the header pin 
>(usually it will be a test point).
>
>Am 05.09.24 um 20:05 schrieb James Coplin:
>> The unpopulated doesn't have enough grab. I suppose I could put a
>couple terminals in there.
>>> I'd use an unpopulated IDC header...
>>>> I was wondering if anyone can point at some product or tell me how
>you
>>>> would handle the problem of exposed unused pins on headers?



From metadata at gmx.com  Fri Sep  6 02:08:34 2024
From: metadata at gmx.com (Neil Harper)
Date: Thu, 5 Sep 2024 20:08:34 -0400
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
Message-ID: <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>

On 2024-09-05 12:55, James Coplin wrote:
> Yesterday, I burned out a board when an exposed piece of connector happened to touch some exposed pins while opening and closing the case.

why does the board need to be powered up when you're opening and closing
the case?



--
/// Neil Harper
/// Every Wave is New Until it Breaks


From james at ticalun.net  Fri Sep  6 02:28:01 2024
From: james at ticalun.net (James Coplin)
Date: Thu, 05 Sep 2024 19:28:01 -0500
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
Message-ID: <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>

It clearly isn't best practice. It's not a synth but an arcade control panel with lots of rgb LEDs and a tangle of point to point wiring no matter how carefully you string it. The controller cards for the LEDs have a pair of large 2 row headers for connecting the 4 wires to the controller for each led. 

There ends up being lots of unused pins and unfortunately while trouble shooting a bad crimp connection, an unhooked spade thermal? numped into some exposed pins on one of the controllers and cooked it. I could be more careful obviously but now I'm also looking for ways to prevent it from happening again regardless of my care level. At some point I'll have it open and have some dangle cable, or a cable will come loose, or I'll be moving something and the threat will reappear again. 

Just to put some numbers on it, there are 43 buttons, each with 6 wires for a total of 258 wires each end of which has a metal spade type conductor of some point. That's a lot of careful handling that I would rather try to mitigate if possible.

James

?Get BlueMail for Android ?

On Sep 5, 2024, 7:13?PM, at 7:13?PM, Neil Harper via Synth-diy <synth-diy at synth-diy.org> wrote:
>On 2024-09-05 12:55, James Coplin wrote:
>> Yesterday, I burned out a board when an exposed piece of connector
>happened to touch some exposed pins while opening and closing the case.
>
>why does the board need to be powered up when you're opening and
>closing
>the case?
>
>
>
>--
>/// Neil Harper
>/// Every Wave is New Until it Breaks
>
>________________________________________________________
>This is the Synth-diy mailing list
>Submit email to: Synth-diy at synth-diy.org
>View archive at: https://synth-diy.org/pipermail/synth-diy/
>Check your settings at:
>https://synth-diy.org/mailman/listinfo/synth-diy
>Selling or trading? Use marketplace at synth-diy.org



From chromatest at chromatest.net  Fri Sep  6 02:48:09 2024
From: chromatest at chromatest.net (Chromatest J. Pantsmaker)
Date: Thu, 5 Sep 2024 17:48:09 -0700
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
Message-ID: <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>

If the pins are unused, why not delete them?

On Thu, Sep 5, 2024 at 5:28?PM James Coplin <james at ticalun.net> wrote:

> It clearly isn't best practice. It's not a synth but an arcade control
> panel with lots of rgb LEDs and a tangle of point to point wiring no matter
> how carefully you string it. The controller cards for the LEDs have a pair
> of large 2 row headers for connecting the 4 wires to the controller for
> each led.
>
> There ends up being lots of unused pins and unfortunately while trouble
> shooting a bad crimp connection, an unhooked spade thermal  numped into
> some exposed pins on one of the controllers and cooked it. I could be more
> careful obviously but now I'm also looking for ways to prevent it from
> happening again regardless of my care level. At some point I'll have it
> open and have some dangle cable, or a cable will come loose, or I'll be
> moving something and the threat will reappear again.
>
> Just to put some numbers on it, there are 43 buttons, each with 6 wires
> for a total of 258 wires each end of which has a metal spade type conductor
> of some point. That's a lot of careful handling that I would rather try to
> mitigate if possible.
>
> James
>
> ?Get BlueMail for Android ?
>
> On Sep 5, 2024, 7:13?PM, at 7:13?PM, Neil Harper via Synth-diy <
> synth-diy at synth-diy.org> wrote:
> >On 2024-09-05 12:55, James Coplin wrote:
> >> Yesterday, I burned out a board when an exposed piece of connector
> >happened to touch some exposed pins while opening and closing the case.
> >
> >why does the board need to be powered up when you're opening and
> >closing
> >the case?
> >
> >
> >
> >--
> >/// Neil Harper
> >/// Every Wave is New Until it Breaks
> >
> >________________________________________________________
> >This is the Synth-diy mailing list
> >Submit email to: Synth-diy at synth-diy.org
> >View archive at: https://synth-diy.org/pipermail/synth-diy/
> >Check your settings at:
> >https://synth-diy.org/mailman/listinfo/synth-diy
> >Selling or trading? Use marketplace at synth-diy.org
>
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>
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From james at ticalun.net  Fri Sep  6 02:52:33 2024
From: james at ticalun.net (James Coplin)
Date: Thu, 05 Sep 2024 19:52:33 -0500
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
Message-ID: <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>

Because they might need to be used in the future.

James

?Get BlueMail for Android ?

On Sep 5, 2024, 7:48?PM, at 7:48?PM, "Chromatest J. Pantsmaker" <chromatest at chromatest.net> wrote:
>If the pins are unused, why not delete them?
>
>On Thu, Sep 5, 2024 at 5:28?PM James Coplin <james at ticalun.net> wrote:
>
>> It clearly isn't best practice. It's not a synth but an arcade
>control
>> panel with lots of rgb LEDs and a tangle of point to point wiring no
>matter
>> how carefully you string it. The controller cards for the LEDs have a
>pair
>> of large 2 row headers for connecting the 4 wires to the controller
>for
>> each led.
>>
>> There ends up being lots of unused pins and unfortunately while
>trouble
>> shooting a bad crimp connection, an unhooked spade thermal  numped
>into
>> some exposed pins on one of the controllers and cooked it. I could be
>more
>> careful obviously but now I'm also looking for ways to prevent it
>from
>> happening again regardless of my care level. At some point I'll have
>it
>> open and have some dangle cable, or a cable will come loose, or I'll
>be
>> moving something and the threat will reappear again.
>>
>> Just to put some numbers on it, there are 43 buttons, each with 6
>wires
>> for a total of 258 wires each end of which has a metal spade type
>conductor
>> of some point. That's a lot of careful handling that I would rather
>try to
>> mitigate if possible.
>>
>> James
>>
>> ?Get BlueMail for Android ?
>>
>> On Sep 5, 2024, 7:13?PM, at 7:13?PM, Neil Harper via Synth-diy <
>> synth-diy at synth-diy.org> wrote:
>> >On 2024-09-05 12:55, James Coplin wrote:
>> >> Yesterday, I burned out a board when an exposed piece of connector
>> >happened to touch some exposed pins while opening and closing the
>case.
>> >
>> >why does the board need to be powered up when you're opening and
>> >closing
>> >the case?
>> >
>> >
>> >
>> >--
>> >/// Neil Harper
>> >/// Every Wave is New Until it Breaks
>> >
>> >________________________________________________________
>> >This is the Synth-diy mailing list
>> >Submit email to: Synth-diy at synth-diy.org
>> >View archive at: https://synth-diy.org/pipermail/synth-diy/
>> >Check your settings at:
>> >https://synth-diy.org/mailman/listinfo/synth-diy
>> >Selling or trading? Use marketplace at synth-diy.org
>>
>>
>> ________________________________________________________
>> This is the Synth-diy mailing list
>> Submit email to: Synth-diy at synth-diy.org
>> View archive at: https://synth-diy.org/pipermail/synth-diy/
>> Check your settings at:
>https://synth-diy.org/mailman/listinfo/synth-diy
>> Selling or trading? Use marketplace at synth-diy.org
>>



From tim.parkhurst at gmail.com  Fri Sep  6 04:12:52 2024
From: tim.parkhurst at gmail.com (Tim Parkhurst)
Date: Thu, 5 Sep 2024 19:12:52 -0700
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
Message-ID: <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>

How about a dab of silicone (RTV)? Would cover the pins, and could be
peeled off later if the connector was needed. Or maybe just a piece of
masking tape. That would stay in place for a while (although it might dry
and fall off after a few years).


Tim (do robots have silicon implants?) Servo
---
"Imagination is more important than knowledge." - Albert Einstein





On Thu, Sep 5, 2024 at 6:01?PM James Coplin <james at ticalun.net> wrote:

> Because they might need to be used in the future.
>
> James
>
> ?Get BlueMail for Android ?
>
> On Sep 5, 2024, 7:48?PM, at 7:48?PM, "Chromatest J. Pantsmaker" <
> chromatest at chromatest.net> wrote:
> >If the pins are unused, why not delete them?
> >
> >On Thu, Sep 5, 2024 at 5:28?PM James Coplin <james at ticalun.net> wrote:
> >
> >> It clearly isn't best practice. It's not a synth but an arcade
> >control
> >> panel with lots of rgb LEDs and a tangle of point to point wiring no
> >matter
> >> how carefully you string it. The controller cards for the LEDs have a
> >pair
> >> of large 2 row headers for connecting the 4 wires to the controller
> >for
> >> each led.
> >>
> >> There ends up being lots of unused pins and unfortunately while
> >trouble
> >> shooting a bad crimp connection, an unhooked spade thermal  numped
> >into
> >> some exposed pins on one of the controllers and cooked it. I could be
> >more
> >> careful obviously but now I'm also looking for ways to prevent it
> >from
> >> happening again regardless of my care level. At some point I'll have
> >it
> >> open and have some dangle cable, or a cable will come loose, or I'll
> >be
> >> moving something and the threat will reappear again.
> >>
> >> Just to put some numbers on it, there are 43 buttons, each with 6
> >wires
> >> for a total of 258 wires each end of which has a metal spade type
> >conductor
> >> of some point. That's a lot of careful handling that I would rather
> >try to
> >> mitigate if possible.
> >>
> >> James
> >>
> >> ?Get BlueMail for Android ?
> >>
> >> On Sep 5, 2024, 7:13?PM, at 7:13?PM, Neil Harper via Synth-diy <
> >> synth-diy at synth-diy.org> wrote:
> >> >On 2024-09-05 12:55, James Coplin wrote:
> >> >> Yesterday, I burned out a board when an exposed piece of connector
> >> >happened to touch some exposed pins while opening and closing the
> >case.
> >> >
> >> >why does the board need to be powered up when you're opening and
> >> >closing
> >> >the case?
> >> >
> >> >
> >> >
> >> >--
> >> >/// Neil Harper
> >> >/// Every Wave is New Until it Breaks
> >> >
> >> >________________________________________________________
> >> >This is the Synth-diy mailing list
> >> >Submit email to: Synth-diy at synth-diy.org
> >> >View archive at: https://synth-diy.org/pipermail/synth-diy/
> >> >Check your settings at:
> >> >https://synth-diy.org/mailman/listinfo/synth-diy
> >> >Selling or trading? Use marketplace at synth-diy.org
> >>
> >>
> >> ________________________________________________________
> >> This is the Synth-diy mailing list
> >> Submit email to: Synth-diy at synth-diy.org
> >> View archive at: https://synth-diy.org/pipermail/synth-diy/
> >> Check your settings at:
> >https://synth-diy.org/mailman/listinfo/synth-diy
> >> Selling or trading? Use marketplace at synth-diy.org
> >>
>
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>
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From cheater00social at gmail.com  Fri Sep  6 14:17:57 2024
From: cheater00social at gmail.com (cheater cheater)
Date: Fri, 6 Sep 2024 14:17:57 +0200
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
Message-ID: <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>

i'm still confused as to how unplugging a thing from the wall is too difficult

if you don't hit the header, next time you'll hit some other conductor

capacitor top

trace

resistor lead

ic lead

it's just a stupid idea to work on live circuits and a major WTF anyways


On Fri, Sep 6, 2024 at 4:25?AM Tim Parkhurst via Synth-diy
<synth-diy at synth-diy.org> wrote:
>
> How about a dab of silicone (RTV)? Would cover the pins, and could be peeled off later if the connector was needed. Or maybe just a piece of masking tape. That would stay in place for a while (although it might dry and fall off after a few years).
>
>
> Tim (do robots have silicon implants?) Servo
> ---
> "Imagination is more important than knowledge." - Albert Einstein
>
>
>
>
>
> On Thu, Sep 5, 2024 at 6:01?PM James Coplin <james at ticalun.net> wrote:
>>
>> Because they might need to be used in the future.
>>
>> James
>>
>> ?Get BlueMail for Android
>>
>> On Sep 5, 2024, 7:48?PM, at 7:48?PM, "Chromatest J. Pantsmaker" <chromatest at chromatest.net> wrote:
>> >If the pins are unused, why not delete them?
>> >
>> >On Thu, Sep 5, 2024 at 5:28?PM James Coplin <james at ticalun.net> wrote:
>> >
>> >> It clearly isn't best practice. It's not a synth but an arcade
>> >control
>> >> panel with lots of rgb LEDs and a tangle of point to point wiring no
>> >matter
>> >> how carefully you string it. The controller cards for the LEDs have a
>> >pair
>> >> of large 2 row headers for connecting the 4 wires to the controller
>> >for
>> >> each led.
>> >>
>> >> There ends up being lots of unused pins and unfortunately while
>> >trouble
>> >> shooting a bad crimp connection, an unhooked spade thermal  numped
>> >into
>> >> some exposed pins on one of the controllers and cooked it. I could be
>> >more
>> >> careful obviously but now I'm also looking for ways to prevent it
>> >from
>> >> happening again regardless of my care level. At some point I'll have
>> >it
>> >> open and have some dangle cable, or a cable will come loose, or I'll
>> >be
>> >> moving something and the threat will reappear again.
>> >>
>> >> Just to put some numbers on it, there are 43 buttons, each with 6
>> >wires
>> >> for a total of 258 wires each end of which has a metal spade type
>> >conductor
>> >> of some point. That's a lot of careful handling that I would rather
>> >try to
>> >> mitigate if possible.
>> >>
>> >> James
>> >>
>> >> ?Get BlueMail for Android
>> >>
>> >> On Sep 5, 2024, 7:13?PM, at 7:13?PM, Neil Harper via Synth-diy <
>> >> synth-diy at synth-diy.org> wrote:
>> >> >On 2024-09-05 12:55, James Coplin wrote:
>> >> >> Yesterday, I burned out a board when an exposed piece of connector
>> >> >happened to touch some exposed pins while opening and closing the
>> >case.
>> >> >
>> >> >why does the board need to be powered up when you're opening and
>> >> >closing
>> >> >the case?
>> >> >
>> >> >
>> >> >
>> >> >--
>> >> >/// Neil Harper
>> >> >/// Every Wave is New Until it Breaks
>> >> >
>> >> >________________________________________________________
>> >> >This is the Synth-diy mailing list
>> >> >Submit email to: Synth-diy at synth-diy.org
>> >> >View archive at: https://synth-diy.org/pipermail/synth-diy/
>> >> >Check your settings at:
>> >> >https://synth-diy.org/mailman/listinfo/synth-diy
>> >> >Selling or trading? Use marketplace at synth-diy.org
>> >>
>> >>
>> >> ________________________________________________________
>> >> This is the Synth-diy mailing list
>> >> Submit email to: Synth-diy at synth-diy.org
>> >> View archive at: https://synth-diy.org/pipermail/synth-diy/
>> >> Check your settings at:
>> >https://synth-diy.org/mailman/listinfo/synth-diy
>> >> Selling or trading? Use marketplace at synth-diy.org
>> >>
>>
>>
>> ________________________________________________________
>> This is the Synth-diy mailing list
>> Submit email to: Synth-diy at synth-diy.org
>> View archive at: https://synth-diy.org/pipermail/synth-diy/
>> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
>> Selling or trading? Use marketplace at synth-diy.org
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org


From tom at electricdruid.net  Fri Sep  6 14:59:19 2024
From: tom at electricdruid.net (Tom Wiltshire)
Date: Fri, 6 Sep 2024 13:59:19 +0100
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
Message-ID: <A2CBB70C-4890-4241-BC81-0EFEE240B888@electricdruid.net>


> On 6 Sep 2024, at 13:17, cheater cheater via Synth-diy <synth-diy at synth-diy.org> wrote:
> 
> i'm still confused as to how unplugging a thing from the wall is too difficult

Yes, that does seem to be the obvious solution!

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From fanwander at mnet-online.de  Fri Sep  6 16:23:22 2024
From: fanwander at mnet-online.de (Florian Anwander)
Date: Fri, 6 Sep 2024 16:23:22 +0200
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
Message-ID: <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>

Hello

Am 06.09.24 um 14:17 schrieb cheater cheater via Synth-diy:
> i'm still confused as to how unplugging a thing from the wall is too 
> difficult 
hmmm, when I am repairing a device and I have to do measurements or 
trimming, I will have to open and close the lid a hundred times to 
change settings on the frontpanel and then get back inside to continue 
my measurement. Of course I don't want to unplug or switch off the 
device, for each move of the lid...

Florian
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From subjectivity at hotmail.com  Fri Sep  6 16:31:04 2024
From: subjectivity at hotmail.com (Dan Snazelle)
Date: Fri, 6 Sep 2024 14:31:04 +0000
Subject: [sdiy] Custom Aluminum Shops?
Message-ID: <PH7PR12MB7188D54BF2A9380AE47D3EC6C89E2@PH7PR12MB7188.namprd12.prod.outlook.com>

Hello All

Feel free to contact me off list if this is too esoteric but I was wondering if anyone has contacts in the USA or Canada for places that can do runs of custom aluminum boxes even better if they can also do powdercoating/etc.


All my old contacts circa 5 years ago seem to have gone under.


thanks


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From mr at analogue.org  Fri Sep  6 17:45:50 2024
From: mr at analogue.org (Mattias Rickardsson)
Date: Fri, 6 Sep 2024 17:45:50 +0200
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
 <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
Message-ID: <CAP92RBUUY9cTSqrejMrEG8QWiMvPdX0NetJ6tedyK_xsWsbKcw@mail.gmail.com>

How could you ever work with electronics without having stuff powered on?

(Try powering off your computers, software guys out there)  ;-)

/mr

Den fre 6 sep. 2024 16:34Florian Anwander <fanwander at mnet-online.de> skrev:

> Hello
>
> Am 06.09.24 um 14:17 schrieb cheater cheater via Synth-diy:
>
> i'm still confused as to how unplugging a thing from the wall is too
> difficult
>
> hmmm, when I am repairing a device and I have to do measurements or
> trimming, I will have to open and close the lid a hundred times to change
> settings on the frontpanel and then get back inside to continue my
> measurement. Of course I don't want to unplug or switch off the device, for
> each move of the lid...
>
> Florian
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>
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From dh at atoav.com  Fri Sep  6 18:14:04 2024
From: dh at atoav.com (David Huss)
Date: Fri, 06 Sep 2024 16:14:04 +0000
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <CAP92RBUUY9cTSqrejMrEG8QWiMvPdX0NetJ6tedyK_xsWsbKcw@mail.gmail.com>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
 <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
 <CAP92RBUUY9cTSqrejMrEG8QWiMvPdX0NetJ6tedyK_xsWsbKcw@mail.gmail.com>
Message-ID: <60E8FED6-8CDB-4CBE-8AED-D4E0282A244E@atoav.com>

If it was just for the workshop I'd get a suitable female connector, cut & grind off the pins and dip the top into plastidip.

Alternatively you should just try to treat powered electrical circuits like raw eggs and ensure your benchtop is spacious/cleared enough that such accidents become less likely.

On September 6, 2024 3:45:50 PM UTC, Mattias Rickardsson <mr at analogue.org> wrote:
>How could you ever work with electronics without having stuff powered on?
>
>(Try powering off your computers, software guys out there)  ;-)
>
>/mr
>
>Den fre 6 sep. 2024 16:34Florian Anwander <fanwander at mnet-online.de> skrev:
>
>> Hello
>>
>> Am 06.09.24 um 14:17 schrieb cheater cheater via Synth-diy:
>>
>> i'm still confused as to how unplugging a thing from the wall is too
>> difficult
>>
>> hmmm, when I am repairing a device and I have to do measurements or
>> trimming, I will have to open and close the lid a hundred times to change
>> settings on the frontpanel and then get back inside to continue my
>> measurement. Of course I don't want to unplug or switch off the device, for
>> each move of the lid...
>>
>> Florian
>> ________________________________________________________
>> This is the Synth-diy mailing list
>> Submit email to: Synth-diy at synth-diy.org
>> View archive at: https://synth-diy.org/pipermail/synth-diy/
>> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
>> Selling or trading? Use marketplace at synth-diy.org
>>


From nathan at idmclassics.net  Fri Sep  6 18:43:16 2024
From: nathan at idmclassics.net (Nathan Trites)
Date: Fri, 6 Sep 2024 12:43:16 -0400
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
 <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
Message-ID: <CAHy3N6AWST-2xVZH5BmmLRxffAaKt1PnQw5qxOwKYh08JLYP6w@mail.gmail.com>

I completely agree, opening and closing the case isn't the issue here -
precaution is. Maneuvering and working with live circuits is an inherent
part of diagnostics and repair, and depending on the device there are
infinite ways to cause shorts during routine work.

Personally, I'm surprised there's 20 posts of advice in this thread and no
one's asked exactly what kind of header/connectors James is working with!
Since it's an old arcade cabinet, I'd assume a mix of edge connectors and
molex? Immediate advice: put heat shrink over the spade terminal. Any
bigger free floating connectors just use larger diameter heat shrink (1"
etc) long enough so it doesn't make contact with other parts. If you need
to easily remove and re-insulate, some kind of tape. Florian's initial
advice is the right move for most friction connector types.

Think thru the scenarios:

If the header is always exposed and could be considered a design flaw or
allowed to happen due to other design choices (e.g. you need to have
various connectors unsecured in order to work on it), having a way to cover
the headers when not in use makes perfect sense. I'd create a dummy
connector of the same type (with crimps inserted if needed), and if the
connector type doesn't have a cover or covered version available, fill the
cable opening with silicone RTV or hot glue.

If they were left exposed in the course of repair and the risk of shorting
is there again... If they're low voltage/current I'd probably just put blue
painters tape over them until they're needed again, or some type of
Kapton, PTFE, or electrical tape which all have other compromises. If
they're higher voltage or current, secure the loose connector as best as
possible so it doesn't pose any risk, or create a dummy connector for the
exposed header and insulate the openings with hot glue or something. As
above, cover any free connectors on cables with appropriately sized heat
shrink.

Nathan


On Fri, Sep 6, 2024 at 10:23?AM Florian Anwander <fanwander at mnet-online.de>
wrote:

> Hello
>
> Am 06.09.24 um 14:17 schrieb cheater cheater via Synth-diy:
>
> i'm still confused as to how unplugging a thing from the wall is too
> difficult
>
> hmmm, when I am repairing a device and I have to do measurements or
> trimming, I will have to open and close the lid a hundred times to change
> settings on the frontpanel and then get back inside to continue my
> measurement. Of course I don't want to unplug or switch off the device, for
> each move of the lid...
>
> Florian
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>
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From declareupdate at gmail.com  Fri Sep  6 19:52:02 2024
From: declareupdate at gmail.com (Chris McDowell)
Date: Fri, 6 Sep 2024 13:52:02 -0400
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <PH7PR12MB7188D54BF2A9380AE47D3EC6C89E2@PH7PR12MB7188.namprd12.prod.outlook.com>
References: <PH7PR12MB7188D54BF2A9380AE47D3EC6C89E2@PH7PR12MB7188.namprd12.prod.outlook.com>
Message-ID: <928D5D3E-E4B3-4CF9-A5CD-4A17643CBCFF@gmail.com>

Replying on-list would be even cooler!

Dan, I have used a shop called Bratek in Denver. They were great to work with, though not very economical in my quantities: https://bratekeng.com/

I also work with these guys a ton: https://www.premiumparts.com/

They are incredible for low run prototype stuff, and cheap for that particularly, but maybe not right for higher quantities. Very much worth quoting with them. People at my work will send them outrageous CAD and their guy Derrick just makes it happen. 

Cheers,
Chris 

> On Sep 6, 2024, at 10:38?AM, Dan Snazelle via Synth-diy <synth-diy at synth-diy.org> wrote:
> 
> ?
> Hello All
> 
> Feel free to contact me off list if this is too esoteric but I was wondering if anyone has contacts in the USA or Canada for places that can do runs of custom aluminum boxes even better if they can also do powdercoating/etc.
> 
> 
> All my old contacts circa 5 years ago seem to have gone under. 
> 
> 
> thanks
> 
> 
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
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From james at ticalun.net  Fri Sep  6 21:12:38 2024
From: james at ticalun.net (James R. Coplin)
Date: Fri, 6 Sep 2024 14:12:38 -0500
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <CAHy3N6AWST-2xVZH5BmmLRxffAaKt1PnQw5qxOwKYh08JLYP6w@mail.gmail.com>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
 <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
 <CAHy3N6AWST-2xVZH5BmmLRxffAaKt1PnQw5qxOwKYh08JLYP6w@mail.gmail.com>
Message-ID: <eaf3397a-fc1f-adba-c425-576869d5d860@ticalun.net>

Basically, the cabinet has two of these installed for LED control.

https://www.ultimarc.com/output/led-and-output-controllers/pacled64/

As you can see, they have two large headers of pins for the led controls 
and since I'm using 2 of them, there are a significant number of unused 
pins. I have to use 2 because some of the leds are 5v and some are 12v. 
The whole cabinet is filled with point to point, crimped on spade type 
connectors. Troubleshooting an intermittent ground connection pretty 
much requires having it on and poking around. Further, because the 
control panel takes a lot of physical use and vibration from button 
presses, disgruntled fist smashing, etc, things can come loose since the 
connection are friction not soldered. The spades do have insulation on 
them to try and prevent shorting but even so, I had a loose connection 
hit the pins at just the right angle that the inside spade connected 
across pins and blew out a board. I probably couldn't do it again if I 
tried but the way my luck goes, I don't want to find out and that's why 
I was looking for solutions.

The corrugated cardboard suggestion seems like a really good one and I 
will probably try that or some foam core. I'll probably just end up 3d 
printing something or use terminal housings that match with the minimum 
number of empty terminals installed for it to grab. The ribbon cable 
type connectors would be great but they aren't meant to go right next to 
each other so probably wont work either.

James

Nathan Trites wrote on 9/6/2024 11:43 AM:
- show quoted text -


Nathan Trites wrote on 9/6/2024 11:43 AM:
> I completely agree, opening and closing the case isn't the issue here 
> - precaution is. Maneuvering and working with live circuits is an 
> inherent part of diagnostics and repair, and depending on the device 
> there are infinite ways to cause shorts during routine work.
>
> Personally, I'm surprised there's 20 posts of advice in this thread 
> and no one's asked exactly what kind of header/connectors James is 
> working with! Since it's an old arcade cabinet, I'd assume a mix of 
> edge connectors and molex? Immediate advice: put heat shrink over the 
> spade terminal. Any bigger free floating connectors just use larger 
> diameter heat shrink (1" etc) long enough so it doesn't make contact 
> with other parts. If you need to easily remove and re-insulate, some 
> kind of tape. Florian's initial advice is the right move for most 
> friction connector types.
>
> Think thru the scenarios:
>
> If the header is always exposed and could be considered a design flaw 
> or allowed to happen due to other design choices (e.g. you need to 
> have various connectors unsecured in order to work on it), having a 
> way to cover the headers when not in use makes perfect sense. I'd 
> create a dummy connector of the same type (with crimps inserted if 
> needed), and if the connector type doesn't have a cover or covered 
> version available, fill the cable opening with silicone RTV or hot glue.
>
> If they were left exposed in the course of repair and the risk of 
> shorting is there again... If they're low voltage/current I'd probably 
> just put blue painters tape over them until they're needed again, or 
> some type of Kapton,?PTFE, or electrical tape which all have other 
> compromises. If they're higher voltage or current, secure the?loose 
> connector as best as possible so it doesn't pose any risk, or create a 
> dummy connector for the exposed header and insulate the openings with 
> hot glue or something. As above, cover any free connectors on cables 
> with appropriately sized heat shrink.
>
> Nathan
>
>
> On Fri, Sep 6, 2024 at 10:23?AM Florian Anwander 
> <fanwander at mnet-online.de <mailto:fanwander at mnet-online.de>> wrote:
>
>     Hello
>
>     Am 06.09.24 um 14:17 schrieb cheater cheater via Synth-diy:
>>     i'm still confused as to how unplugging a thing from the wall is
>>     too difficult 
>     hmmm, when I am repairing a device and I have to do measurements
>     or trimming, I will have to open and close the lid a hundred times
>     to change settings on the frontpanel and then get back inside to
>     continue my measurement. Of course I don't want to unplug or
>     switch off the device, for each move of the lid...
>
>     Florian
>     ________________________________________________________
>     This is the Synth-diy mailing list
>     Submit email to: Synth-diy at synth-diy.org
>     <mailto:Synth-diy at synth-diy.org>
>     View archive at: https://synth-diy.org/pipermail/synth-diy/
>     Check your settings at:
>     https://synth-diy.org/mailman/listinfo/synth-diy
>     Selling or trading? Use marketplace at synth-diy.org
>     <mailto:marketplace at synth-diy.org>
>
>
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org

-- 
Sent from Postbox <https://www.postbox-inc.com>
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From dh at atoav.com  Fri Sep  6 23:06:20 2024
From: dh at atoav.com (David Huss)
Date: Fri, 06 Sep 2024 21:06:20 +0000
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <eaf3397a-fc1f-adba-c425-576869d5d860@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
 <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
 <CAHy3N6AWST-2xVZH5BmmLRxffAaKt1PnQw5qxOwKYh08JLYP6w@mail.gmail.com>
 <eaf3397a-fc1f-adba-c425-576869d5d860@ticalun.net>
Message-ID: <D6018E9D-9887-4ADB-AE76-E2E4EF953CD7@atoav.com>

If the cables are long enough often a good solution is to provide a sort of strain relief that ensures that that even if there is significant vibration there is no pull on the cables.

If cables do become loose I would consider applying moderate amounts of hot glue in the right places. If you plan to 3D print something anyways you could probably create a part that holds in the connectors, covers the pins and provides strain relief at the same time.

As for 12V/5V LEDs: it is quite likely you can drive the 5V LEDs from the 12V board with the right value resistors in series. Whether that is worth the effort, I can't tell you.

On September 6, 2024 7:12:38 PM UTC, "James R. Coplin" <james at ticalun.net> wrote:
>Basically, the cabinet has two of these installed for LED control.
>
>https://www.ultimarc.com/output/led-and-output-controllers/pacled64/
>
>As you can see, they have two large headers of pins for the led controls and since I'm using 2 of them, there are a significant number of unused pins. I have to use 2 because some of the leds are 5v and some are 12v. The whole cabinet is filled with point to point, crimped on spade type connectors. Troubleshooting an intermittent ground connection pretty much requires having it on and poking around. Further, because the control panel takes a lot of physical use and vibration from button presses, disgruntled fist smashing, etc, things can come loose since the connection are friction not soldered. The spades do have insulation on them to try and prevent shorting but even so, I had a loose connection hit the pins at just the right angle that the inside spade connected across pins and blew out a board. I probably couldn't do it again if I tried but the way my luck goes, I don't want to find out and that's why I was looking for solutions.
>
>The corrugated cardboard suggestion seems like a really good one and I will probably try that or some foam core. I'll probably just end up 3d printing something or use terminal housings that match with the minimum number of empty terminals installed for it to grab. The ribbon cable type connectors would be great but they aren't meant to go right next to each other so probably wont work either.
>
>James
>
>Nathan Trites wrote on 9/6/2024 11:43 AM:
>- show quoted text -
>
>
>Nathan Trites wrote on 9/6/2024 11:43 AM:
>> I completely agree, opening and closing the case isn't the issue here - precaution is. Maneuvering and working with live circuits is an inherent part of diagnostics and repair, and depending on the device there are infinite ways to cause shorts during routine work.
>> 
>> Personally, I'm surprised there's 20 posts of advice in this thread and no one's asked exactly what kind of header/connectors James is working with! Since it's an old arcade cabinet, I'd assume a mix of edge connectors and molex? Immediate advice: put heat shrink over the spade terminal. Any bigger free floating connectors just use larger diameter heat shrink (1" etc) long enough so it doesn't make contact with other parts. If you need to easily remove and re-insulate, some kind of tape. Florian's initial advice is the right move for most friction connector types.
>> 
>> Think thru the scenarios:
>> 
>> If the header is always exposed and could be considered a design flaw or allowed to happen due to other design choices (e.g. you need to have various connectors unsecured in order to work on it), having a way to cover the headers when not in use makes perfect sense. I'd create a dummy connector of the same type (with crimps inserted if needed), and if the connector type doesn't have a cover or covered version available, fill the cable opening with silicone RTV or hot glue.
>> 
>> If they were left exposed in the course of repair and the risk of shorting is there again... If they're low voltage/current I'd probably just put blue painters tape over them until they're needed again, or some type of Kapton,?PTFE, or electrical tape which all have other compromises. If they're higher voltage or current, secure the?loose connector as best as possible so it doesn't pose any risk, or create a dummy connector for the exposed header and insulate the openings with hot glue or something. As above, cover any free connectors on cables with appropriately sized heat shrink.
>> 
>> Nathan
>> 
>> 
>> On Fri, Sep 6, 2024 at 10:23?AM Florian Anwander <fanwander at mnet-online.de <mailto:fanwander at mnet-online.de>> wrote:
>> 
>>     Hello
>> 
>>     Am 06.09.24 um 14:17 schrieb cheater cheater via Synth-diy:
>>>     i'm still confused as to how unplugging a thing from the wall is
>>>     too difficult 
>>     hmmm, when I am repairing a device and I have to do measurements
>>     or trimming, I will have to open and close the lid a hundred times
>>     to change settings on the frontpanel and then get back inside to
>>     continue my measurement. Of course I don't want to unplug or
>>     switch off the device, for each move of the lid...
>> 
>>     Florian
>>     ________________________________________________________
>>     This is the Synth-diy mailing list
>>     Submit email to: Synth-diy at synth-diy.org
>>     <mailto:Synth-diy at synth-diy.org>
>>     View archive at: https://synth-diy.org/pipermail/synth-diy/
>>     Check your settings at:
>>     https://synth-diy.org/mailman/listinfo/synth-diy
>>     Selling or trading? Use marketplace at synth-diy.org
>>     <mailto:marketplace at synth-diy.org>
>> 
>> 
>> 
>> ________________________________________________________
>> This is the Synth-diy mailing list
>> Submit email to: Synth-diy at synth-diy.org
>> View archive at: https://synth-diy.org/pipermail/synth-diy/
>> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
>> Selling or trading? Use marketplace at synth-diy.org
>


From grant at musictechnologiesgroup.com  Fri Sep  6 23:50:40 2024
From: grant at musictechnologiesgroup.com (grant musictechnologiesgroup.com)
Date: Fri, 6 Sep 2024 21:50:40 +0000
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <eaf3397a-fc1f-adba-c425-576869d5d860@ticalun.net>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
 <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
 <CAHy3N6AWST-2xVZH5BmmLRxffAaKt1PnQw5qxOwKYh08JLYP6w@mail.gmail.com>
 <eaf3397a-fc1f-adba-c425-576869d5d860@ticalun.net>
Message-ID: <em48eaaf76-777b-4254-bfbf-178a69a0643b@89265e87.com>

Hmmm. I've never seen anyone use spade's on header pins, but I suppose it's no worse than the dreaded "Dupont" ones.

Although larger and more expensive, those locking headers pins would be much better:

https://www.mouser.com/ProductDetail/538-70543-0036

https://www.mouser.com/ProductDetail/538-50-57-9402

Crimping is not that hard.

GB


------ Original Message ------
From "James R. Coplin" <james at ticalun.net<mailto:james at ticalun.net>>
To "synth-diy at synth-diy.org<mailto:synth-diy at synth-diy.org>" <synth-diy at synth-diy.org<mailto:synth-diy at synth-diy.org>>
Date 9/6/2024 12:12:38 PM
Subject Re: [sdiy] Covers / shroud for unused header pins?

Basically, the cabinet has two of these installed for LED control.

https://www.ultimarc.com/output/led-and-output-controllers/pacled64/

As you can see, they have two large headers of pins for the led controls and since I'm using 2 of them, there are a significant number of unused pins. I have to use 2 because some of the leds are 5v and some are 12v. The whole cabinet is filled with point to point, crimped on spade type connectors. Troubleshooting an intermittent ground connection pretty much requires having it on and poking around. Further, because the control panel takes a lot of physical use and vibration from button presses, disgruntled fist smashing, etc, things can come loose since the connection are friction not soldered. The spades do have insulation on them to try and prevent shorting but even so, I had a loose connection hit the pins at just the right angle that the inside spade connected across pins and blew out a board. I probably couldn't do it again if I tried but the way my luck goes, I don't want to find out and that's why I was looking for solutions.

The corrugated cardboard suggestion seems like a really good one and I will probably try that or some foam core. I'll probably just end up 3d printing something or use terminal housings that match with the minimum number of empty terminals installed for it to grab. The ribbon cable type connectors would be great but they aren't meant to go right next to each other so probably wont work either.

James

Nathan Trites wrote on 9/6/2024 11:43 AM:
- show quoted text -


Nathan Trites wrote on 9/6/2024 11:43 AM:
I completely agree, opening and closing the case isn't the issue here - precaution is. Maneuvering and working with live circuits is an inherent part of diagnostics and repair, and depending on the device there are infinite ways to cause shorts during routine work.

Personally, I'm surprised there's 20 posts of advice in this thread and no one's asked exactly what kind of header/connectors James is working with! Since it's an old arcade cabinet, I'd assume a mix of edge connectors and molex? Immediate advice: put heat shrink over the spade terminal. Any bigger free floating connectors just use larger diameter heat shrink (1" etc) long enough so it doesn't make contact with other parts. If you need to easily remove and re-insulate, some kind of tape. Florian's initial advice is the right move for most friction connector types.

Think thru the scenarios:

If the header is always exposed and could be considered a design flaw or allowed to happen due to other design choices (e.g. you need to have various connectors unsecured in order to work on it), having a way to cover the headers when not in use makes perfect sense. I'd create a dummy connector of the same type (with crimps inserted if needed), and if the connector type doesn't have a cover or covered version available, fill the cable opening with silicone RTV or hot glue.

If they were left exposed in the course of repair and the risk of shorting is there again... If they're low voltage/current I'd probably just put blue painters tape over them until they're needed again, or some type of Kapton, PTFE, or electrical tape which all have other compromises. If they're higher voltage or current, secure the loose connector as best as possible so it doesn't pose any risk, or create a dummy connector for the exposed header and insulate the openings with hot glue or something. As above, cover any free connectors on cables with appropriately sized heat shrink.

Nathan


On Fri, Sep 6, 2024 at 10:23?AM Florian Anwander <fanwander at mnet-online.de<mailto:fanwander at mnet-online.de>> wrote:
Hello

Am 06.09.24 um 14:17 schrieb cheater cheater via Synth-diy:
i'm still confused as to how unplugging a thing from the wall is too difficult
hmmm, when I am repairing a device and I have to do measurements or trimming, I will have to open and close the lid a hundred times to change settings on the frontpanel and then get back inside to continue my measurement. Of course I don't want to unplug or switch off the device, for each move of the lid...

Florian
________________________________________________________
This is the Synth-diy mailing list
Submit email to: Synth-diy at synth-diy.org<mailto:Synth-diy at synth-diy.org>
View archive at: https://synth-diy.org/pipermail/synth-diy/
Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
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________________________________________________________
This is the Synth-diy mailing list
Submit email to:
Synth-diy at synth-diy.org<mailto:Synth-diy at synth-diy.org>
View archive at: https://synth-diy.org/pipermail/synth-diy/
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From james at ticalun.net  Fri Sep  6 23:53:51 2024
From: james at ticalun.net (James Coplin)
Date: Fri, 06 Sep 2024 16:53:51 -0500
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <em48eaaf76-777b-4254-bfbf-178a69a0643b@89265e87.com>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
 <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
 <CAHy3N6AWST-2xVZH5BmmLRxffAaKt1PnQw5qxOwKYh08JLYP6w@mail.gmail.com>
 <eaf3397a-fc1f-adba-c425-576869d5d860@ticalun.net>
 <em48eaaf76-777b-4254-bfbf-178a69a0643b@89265e87.com>
Message-ID: <f96b399e-ee34-49d8-8f41-43b9ac923b82@ticalun.net>

The spades are on the other end, where the button leads are. These headers are DuPont type housings. The spades was dangling and swung back and hit the header pins.

James

?Get BlueMail for Android ?

On Sep 6, 2024, 4:50?PM, at 4:50?PM, "grant musictechnologiesgroup.com" <grant at musictechnologiesgroup.com> wrote:
>Hmmm. I've never seen anyone use spade's on header pins, but I suppose
>it's no worse than the dreaded "Dupont" ones.
>
>Although larger and more expensive, those locking headers pins would be
>much better:
>
>https://www.mouser.com/ProductDetail/538-70543-0036
>
>https://www.mouser.com/ProductDetail/538-50-57-9402
>
>Crimping is not that hard.
>
>GB
>
>
>------ Original Message ------
>From "James R. Coplin" <james at ticalun.net<mailto:james at ticalun.net>>
>To "synth-diy at synth-diy.org<mailto:synth-diy at synth-diy.org>"
><synth-diy at synth-diy.org<mailto:synth-diy at synth-diy.org>>
>Date 9/6/2024 12:12:38 PM
>Subject Re: [sdiy] Covers / shroud for unused header pins?
>
>Basically, the cabinet has two of these installed for LED control.
>
>https://www.ultimarc.com/output/led-and-output-controllers/pacled64/
>
>As you can see, they have two large headers of pins for the led
>controls and since I'm using 2 of them, there are a significant number
>of unused pins. I have to use 2 because some of the leds are 5v and
>some are 12v. The whole cabinet is filled with point to point, crimped
>on spade type connectors. Troubleshooting an intermittent ground
>connection pretty much requires having it on and poking around.
>Further, because the control panel takes a lot of physical use and
>vibration from button presses, disgruntled fist smashing, etc, things
>can come loose since the connection are friction not soldered. The
>spades do have insulation on them to try and prevent shorting but even
>so, I had a loose connection hit the pins at just the right angle that
>the inside spade connected across pins and blew out a board. I probably
>couldn't do it again if I tried but the way my luck goes, I don't want
>to find out and that's why I was looking for solutions.
>
>The corrugated cardboard suggestion seems like a really good one and I
>will probably try that or some foam core. I'll probably just end up 3d
>printing something or use terminal housings that match with the minimum
>number of empty terminals installed for it to grab. The ribbon cable
>type connectors would be great but they aren't meant to go right next
>to each other so probably wont work either.
>
>James
>
>Nathan Trites wrote on 9/6/2024 11:43 AM:
>- show quoted text -
>
>
>Nathan Trites wrote on 9/6/2024 11:43 AM:
>I completely agree, opening and closing the case isn't the issue here -
>precaution is. Maneuvering and working with live circuits is an
>inherent part of diagnostics and repair, and depending on the device
>there are infinite ways to cause shorts during routine work.
>
>Personally, I'm surprised there's 20 posts of advice in this thread and
>no one's asked exactly what kind of header/connectors James is working
>with! Since it's an old arcade cabinet, I'd assume a mix of edge
>connectors and molex? Immediate advice: put heat shrink over the spade
>terminal. Any bigger free floating connectors just use larger diameter
>heat shrink (1" etc) long enough so it doesn't make contact with other
>parts. If you need to easily remove and re-insulate, some kind of tape.
>Florian's initial advice is the right move for most friction connector
>types.
>
>Think thru the scenarios:
>
>If the header is always exposed and could be considered a design flaw
>or allowed to happen due to other design choices (e.g. you need to have
>various connectors unsecured in order to work on it), having a way to
>cover the headers when not in use makes perfect sense. I'd create a
>dummy connector of the same type (with crimps inserted if needed), and
>if the connector type doesn't have a cover or covered version
>available, fill the cable opening with silicone RTV or hot glue.
>
>If they were left exposed in the course of repair and the risk of
>shorting is there again... If they're low voltage/current I'd probably
>just put blue painters tape over them until they're needed again, or
>some type of Kapton, PTFE, or electrical tape which all have other
>compromises. If they're higher voltage or current, secure the loose
>connector as best as possible so it doesn't pose any risk, or create a
>dummy connector for the exposed header and insulate the openings with
>hot glue or something. As above, cover any free connectors on cables
>with appropriately sized heat shrink.
>
>Nathan
>
>
>On Fri, Sep 6, 2024 at 10:23?AM Florian Anwander
><fanwander at mnet-online.de<mailto:fanwander at mnet-online.de>> wrote:
>Hello
>
>Am 06.09.24 um 14:17 schrieb cheater cheater via Synth-diy:
>i'm still confused as to how unplugging a thing from the wall is too
>difficult
>hmmm, when I am repairing a device and I have to do measurements or
>trimming, I will have to open and close the lid a hundred times to
>change settings on the frontpanel and then get back inside to continue
>my measurement. Of course I don't want to unplug or switch off the
>device, for each move of the lid...
>
>Florian
>________________________________________________________
>This is the Synth-diy mailing list
>Submit email to:
>Synth-diy at synth-diy.org<mailto:Synth-diy at synth-diy.org>
>View archive at: https://synth-diy.org/pipermail/synth-diy/
>Check your settings at:
>https://synth-diy.org/mailman/listinfo/synth-diy
>Selling or trading? Use
>marketplace at synth-diy.org<mailto:marketplace at synth-diy.org>
>
>
>
>________________________________________________________
>This is the Synth-diy mailing list
>Submit email to:
>Synth-diy at synth-diy.org<mailto:Synth-diy at synth-diy.org>
>View archive at: https://synth-diy.org/pipermail/synth-diy/
>Check your settings at:
>https://synth-diy.org/mailman/listinfo/synth-diy
>Selling or trading? Use
>marketplace at synth-diy.org<mailto:marketplace at synth-diy.org>
>
>
>--
>Sent from Postbox<https://www.postbox-inc.com>



From tim.parkhurst at gmail.com  Sat Sep  7 06:05:08 2024
From: tim.parkhurst at gmail.com (Tim Parkhurst)
Date: Fri, 6 Sep 2024 21:05:08 -0700
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <PH7PR12MB7188D54BF2A9380AE47D3EC6C89E2@PH7PR12MB7188.namprd12.prod.outlook.com>
References: <PH7PR12MB7188D54BF2A9380AE47D3EC6C89E2@PH7PR12MB7188.namprd12.prod.outlook.com>
Message-ID: <CACDGQT_q0-+u0ZxtEzY9hPonuAibFKamGn5+_v3gHghHrdQ=Yw@mail.gmail.com>

Hey Dan,

Looks like Small Bear Electronics is still (back?) in business, and you
could probably get some drilled and painted enclosures there. They also
offer drill jigs for a few enclosure sizes, so that looks like a cool way
to knock out a prototype or two.

https://smallbear-electronics.mybigcommerce.com/enclosures/

Tim (let's get drill jiggy with it) Servo
---
"Imagination is more important than knowledge." - Albert Einstein





On Fri, Sep 6, 2024 at 7:40?AM Dan Snazelle via Synth-diy <
synth-diy at synth-diy.org> wrote:

> Hello All
>
> Feel free to contact me off list if this is too esoteric but I was
> wondering if anyone has contacts in the USA or Canada for places that can
> do runs of custom aluminum boxes even better if they can also do
> powdercoating/etc.
>
>
> All my old contacts circa 5 years ago seem to have gone under.
>
>
> thanks
>
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>
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From subjectivity at hotmail.com  Sat Sep  7 06:58:27 2024
From: subjectivity at hotmail.com (loss)
Date: Sat, 7 Sep 2024 00:58:27 -0400
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <CACDGQT_q0-+u0ZxtEzY9hPonuAibFKamGn5+_v3gHghHrdQ=Yw@mail.gmail.com>
References: <PH7PR12MB7188D54BF2A9380AE47D3EC6C89E2@PH7PR12MB7188.namprd12.prod.outlook.com>
 <CACDGQT_q0-+u0ZxtEzY9hPonuAibFKamGn5+_v3gHghHrdQ=Yw@mail.gmail.com>
Message-ID: <CADwb0P1tisD8WR6Q1E-0_KBDC8ksNdVY1FKZYzY4gg7hH7wF6w@mail.gmail.com>

thanks for all the responses.

At the moment I am trying to do non-hammond style enclosures

 (but getting some pre-drilled powder coated hammond style boxes is always
useful too so thanks for that Tim--AND OMG those drill jigs look like such
a good idea! def gonna try that)



in response to those who sent me aluminum bending places-- do you also use
them for powerdercoating and silkscreen?

It might be too much to ask (or it might not exist these days) but I am
dreaming of finding a place I could get them to do metal., powder AND
silkscreen (or that new printing process for the graphics.... )


a man can dream :)

thanks



On Sat, Sep 7, 2024 at 12:05?AM Tim Parkhurst <tim.parkhurst at gmail.com>
wrote:

> Hey Dan,
>
> Looks like Small Bear Electronics is still (back?) in business, and you
> could probably get some drilled and painted enclosures there. They also
> offer drill jigs for a few enclosure sizes, so that looks like a cool way
> to knock out a prototype or two.
>
> https://smallbear-electronics.mybigcommerce.com/enclosures/
>
> Tim (let's get drill jiggy with it) Servo
> ---
> "Imagination is more important than knowledge." - Albert Einstein
>
>
>
>
>
> On Fri, Sep 6, 2024 at 7:40?AM Dan Snazelle via Synth-diy <
> synth-diy at synth-diy.org> wrote:
>
>> Hello All
>>
>> Feel free to contact me off list if this is too esoteric but I was
>> wondering if anyone has contacts in the USA or Canada for places that can
>> do runs of custom aluminum boxes even better if they can also do
>> powdercoating/etc.
>>
>>
>> All my old contacts circa 5 years ago seem to have gone under.
>>
>>
>> thanks
>>
>>
>> ________________________________________________________
>> This is the Synth-diy mailing list
>> Submit email to: Synth-diy at synth-diy.org
>> View archive at: https://synth-diy.org/pipermail/synth-diy/
>> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
>> Selling or trading? Use marketplace at synth-diy.org
>>
>
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From cheater00social at gmail.com  Sat Sep  7 10:11:08 2024
From: cheater00social at gmail.com (cheater cheater)
Date: Sat, 7 Sep 2024 10:11:08 +0200
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
 <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
Message-ID: <CAGn5V--gt=tsK5tPBPqcOxiwFuhaC4qobfkNyGOW3uHZ-d7AtQ@mail.gmail.com>

On Fri, Sep 6, 2024 at 4:36?PM Florian Anwander
<fanwander at mnet-online.de> wrote:
>
> Hello
>
> Am 06.09.24 um 14:17 schrieb cheater cheater via Synth-diy:
>
> i'm still confused as to how unplugging a thing from the wall is too difficult
>
> hmmm, when I am repairing a device and I have to do measurements or trimming, I will have to open and close the lid a hundred times to change settings on the frontpanel and then get back inside to continue my measurement. Of course I don't want to unplug or switch off the device, for each move of the lid...

He wasn't measuring or whatever, he was closing and opening the thing
while it was at power.

> Florian
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org


From fanwander at mnet-online.de  Sat Sep  7 17:13:03 2024
From: fanwander at mnet-online.de (Florian Anwander)
Date: Sat, 7 Sep 2024 17:13:03 +0200
Subject: [sdiy] Covers / shroud for unused header pins?
In-Reply-To: <CAGn5V--gt=tsK5tPBPqcOxiwFuhaC4qobfkNyGOW3uHZ-d7AtQ@mail.gmail.com>
References: <778d1de8-3754-4b1b-93ee-a559de069930@ticalun.net>
 <6fda58a1-6ecd-483b-893e-b9d2dabf8d3b@gmx.com>
 <a8248a68-0a33-45eb-8f99-95943f8abd96@ticalun.net>
 <CADpm=3H8i5wQC8QEqSLDquCBqBMXhH0CgPBNsRiota6Zt9EZ1w@mail.gmail.com>
 <c388bb99-3513-4c21-92e9-4a8760cc64a2@ticalun.net>
 <CACDGQT96JLq+ef0YYTTUZfq=aVSDzD8gsG3GJF2zNEVQktjFmA@mail.gmail.com>
 <CAGn5V-9kBrvXx3ueEpwuweWf_Ru6K-FufQp4FxaOsOa84UKG7g@mail.gmail.com>
 <1de0de56-fa6a-4ce4-a572-9c26493407bd@mnet-online.de>
 <CAGn5V--gt=tsK5tPBPqcOxiwFuhaC4qobfkNyGOW3uHZ-d7AtQ@mail.gmail.com>
Message-ID: <d7afc8ca-5218-43d7-915b-bd1372c5693b@mnet-online.de>

Hi

Am 07.09.24 um 10:11 schrieb cheater cheater:
> He wasn't measuring or whatever, he was closing and opening the thing
> while it was at power.
yes. that is what you have to do all the time with some gear. I am at a 
restoring a OB-Xa. I can't tell how may times per hour I have to open 
and close the thing while tests and measurements.

Florian
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From declareupdate at gmail.com  Sat Sep  7 20:20:38 2024
From: declareupdate at gmail.com (Chris McDowell)
Date: Sat, 7 Sep 2024 14:20:38 -0400
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <CADwb0P1tisD8WR6Q1E-0_KBDC8ksNdVY1FKZYzY4gg7hH7wF6w@mail.gmail.com>
References: <CADwb0P1tisD8WR6Q1E-0_KBDC8ksNdVY1FKZYzY4gg7hH7wF6w@mail.gmail.com>
Message-ID: <9728F780-1B09-4D5C-9B3D-0DB83B1FD079@gmail.com>

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From thx1138 at earthlink.net  Sat Sep  7 20:59:48 2024
From: thx1138 at earthlink.net (TERRY SHULTZ)
Date: Sat, 7 Sep 2024 11:59:48 -0700
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <9728F780-1B09-4D5C-9B3D-0DB83B1FD079@gmail.com>
References: <CADwb0P1tisD8WR6Q1E-0_KBDC8ksNdVY1FKZYzY4gg7hH7wF6w@mail.gmail.com>
 <9728F780-1B09-4D5C-9B3D-0DB83B1FD079@gmail.com>
Message-ID: <768A75B5-BCE2-44C5-BE36-D34801379F19@earthlink.net>

Hi Chris,

We have used Neal Feay in Santa Barbara area https://www.nealfeay.com <https://www.nealfeay.com/> for our most complex and exotic panels 

And you guys might want to look at Front Panel Express. I believe their tools are free for design and layout.

Just my 2 cents.

Regards,

Terry



> On Sep 7, 2024, at 11:20 AM, Chris McDowell via Synth-diy <synth-diy at synth-diy.org <mailto:synth-diy at synth-diy.org>> wrote:
> 
> Bratek and Premium (both linked in my last email) are full service, like do whatever you want kind of places. Premium is insane and will do -anything-. anodize, powder coat, silk screen, cable assemblies, 3D printing, injection molding, wire EDM, really anything. those are all things I've had Premium do in the past year and they're always awesome. 
> 
> Cheers,
> Chris 
> 
>> On Sep 7, 2024, at 1:01?AM, loss via Synth-diy <synth-diy at synth-diy.org <mailto:synth-diy at synth-diy.org>> wrote:
>> 
>> ?
>> thanks for all the responses. 
>> 
>> At the moment I am trying to do non-hammond style enclosures
>> 
>>  (but getting some pre-drilled powder coated hammond style boxes is always useful too so thanks for that Tim--AND OMG those drill jigs look like such a good idea! def gonna try that)
>> 
>> 
>> 
>> in response to those who sent me aluminum bending places-- do you also use them for powerdercoating and silkscreen? 
>> 
>> It might be too much to ask (or it might not exist these days) but I am dreaming of finding a place I could get them to do metal., powder AND silkscreen (or that new printing process for the graphics.... )
>> 
>> 
>> a man can dream :)
>> 
>> thanks
>> 
>> 
>> 
>> On Sat, Sep 7, 2024 at 12:05?AM Tim Parkhurst <tim.parkhurst at gmail.com <mailto:tim.parkhurst at gmail.com>> wrote:
>> Hey Dan,
>> 
>> Looks like Small Bear Electronics is still (back?) in business, and you could probably get some drilled and painted enclosures there. They also offer drill jigs for a few enclosure sizes, so that looks like a cool way to knock out a prototype or two. 
>> 
>> https://smallbear-electronics.mybigcommerce.com/enclosures/ <https://smallbear-electronics.mybigcommerce.com/enclosures/>
>> 
>> Tim (let's get drill jiggy with it) Servo
>> ---
>> "Imagination is more important than knowledge." - Albert Einstein
>> 
>> 
>> 
>> 
>> 
>> On Fri, Sep 6, 2024 at 7:40?AM Dan Snazelle via Synth-diy <synth-diy at synth-diy.org <mailto:synth-diy at synth-diy.org>> wrote:
>> Hello All
>> 
>> Feel free to contact me off list if this is too esoteric but I was wondering if anyone has contacts in the USA or Canada for places that can do runs of custom aluminum boxes even better if they can also do powdercoating/etc.
>> 
>> 
>> All my old contacts circa 5 years ago seem to have gone under. 
>> 
>> 
>> thanks
>> 
>> 
>> ________________________________________________________
>> This is the Synth-diy mailing list
>> Submit email to: Synth-diy at synth-diy.org <mailto:Synth-diy at synth-diy.org>
>> View archive at: https://synth-diy.org/pipermail/synth-diy/ <https://synth-diy.org/pipermail/synth-diy/>
>> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy <https://synth-diy.org/mailman/listinfo/synth-diy>
>> Selling or trading? Use marketplace at synth-diy.org <mailto:marketplace at synth-diy.org>
>> ________________________________________________________
>> This is the Synth-diy mailing list
>> Submit email to: Synth-diy at synth-diy.org <mailto:Synth-diy at synth-diy.org>
>> View archive at: https://synth-diy.org/pipermail/synth-diy/ <https://synth-diy.org/pipermail/synth-diy/>
>> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy <https://synth-diy.org/mailman/listinfo/synth-diy>
>> Selling or trading? Use marketplace at synth-diy.org <mailto:marketplace at synth-diy.org>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org <mailto:Synth-diy at synth-diy.org>
> View archive at: https://synth-diy.org/pipermail/synth-diy/ <https://synth-diy.org/pipermail/synth-diy/>
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy <https://synth-diy.org/mailman/listinfo/synth-diy>
> Selling or trading? Use marketplace at synth-diy.org <mailto:marketplace at synth-diy.org>

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From cfo at synthcube.com  Sat Sep  7 21:21:32 2024
From: cfo at synthcube.com (Chris H. Park)
Date: Sat, 7 Sep 2024 19:21:32 +0000
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <768A75B5-BCE2-44C5-BE36-D34801379F19@earthlink.net>
References: <CADwb0P1tisD8WR6Q1E-0_KBDC8ksNdVY1FKZYzY4gg7hH7wF6w@mail.gmail.com>
 <9728F780-1B09-4D5C-9B3D-0DB83B1FD079@gmail.com>
 <768A75B5-BCE2-44C5-BE36-D34801379F19@earthlink.net>
Message-ID: <3E5C73E8-436D-4765-B2E3-C1280C229466@synthcube.com>

Thanks Tim for the callout on Small Bear! We try to supply useful things. Full service enclosure + powder coat + silkscreen and/or UV print hard to find in one spot but Disaster Area Designs does that. Pedal Parts Plus used to but just closed their retail offerings to focus on larger scale private boutique pedal customers.


Sent from my iPhone

On Sep 7, 2024, at 2:09?PM, TERRY SHULTZ via Synth-diy <synth-diy at synth-diy.org> wrote:

?
Hi Chris,

We have used Neal Feay in Santa Barbara area https://www.nealfeay.com<https://www.nealfeay.com/> for our most complex and exotic panels

And you guys might want to look at Front Panel Express. I believe their tools are free for design and layout.

Just my 2 cents.

Regards,

Terry



On Sep 7, 2024, at 11:20 AM, Chris McDowell via Synth-diy <synth-diy at synth-diy.org<mailto:synth-diy at synth-diy.org>> wrote:

Bratek and Premium (both linked in my last email) are full service, like do whatever you want kind of places. Premium is insane and will do -anything-. anodize, powder coat, silk screen, cable assemblies, 3D printing, injection molding, wire EDM, really anything. those are all things I've had Premium do in the past year and they're always awesome.

Cheers,
Chris

On Sep 7, 2024, at 1:01?AM, loss via Synth-diy <synth-diy at synth-diy.org<mailto:synth-diy at synth-diy.org>> wrote:

?
thanks for all the responses.

At the moment I am trying to do non-hammond style enclosures

 (but getting some pre-drilled powder coated hammond style boxes is always useful too so thanks for that Tim--AND OMG those drill jigs look like such a good idea! def gonna try that)



in response to those who sent me aluminum bending places-- do you also use them for powerdercoating and silkscreen?

It might be too much to ask (or it might not exist these days) but I am dreaming of finding a place I could get them to do metal., powder AND silkscreen (or that new printing process for the graphics.... )


a man can dream :)

thanks



On Sat, Sep 7, 2024 at 12:05?AM Tim Parkhurst <tim.parkhurst at gmail.com<mailto:tim.parkhurst at gmail.com>> wrote:
Hey Dan,

Looks like Small Bear Electronics is still (back?) in business, and you could probably get some drilled and painted enclosures there. They also offer drill jigs for a few enclosure sizes, so that looks like a cool way to knock out a prototype or two.

https://smallbear-electronics.mybigcommerce.com/enclosures/

Tim (let's get drill jiggy with it) Servo
---
"Imagination is more important than knowledge." - Albert Einstein





On Fri, Sep 6, 2024 at 7:40?AM Dan Snazelle via Synth-diy <synth-diy at synth-diy.org<mailto:synth-diy at synth-diy.org>> wrote:
Hello All

Feel free to contact me off list if this is too esoteric but I was wondering if anyone has contacts in the USA or Canada for places that can do runs of custom aluminum boxes even better if they can also do powdercoating/etc.


All my old contacts circa 5 years ago seem to have gone under.


thanks


________________________________________________________
This is the Synth-diy mailing list
Submit email to: Synth-diy at synth-diy.org<mailto:Synth-diy at synth-diy.org>
View archive at: https://synth-diy.org/pipermail/synth-diy/
Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
Selling or trading? Use marketplace at synth-diy.org<mailto:marketplace at synth-diy.org>
________________________________________________________
This is the Synth-diy mailing list
Submit email to: Synth-diy at synth-diy.org<mailto:Synth-diy at synth-diy.org>
View archive at: https://synth-diy.org/pipermail/synth-diy/
Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
Selling or trading? Use marketplace at synth-diy.org<mailto:marketplace at synth-diy.org>
________________________________________________________
This is the Synth-diy mailing list
Submit email to: Synth-diy at synth-diy.org<mailto:Synth-diy at synth-diy.org>
View archive at: https://synth-diy.org/pipermail/synth-diy/
Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
Selling or trading? Use marketplace at synth-diy.org<mailto:marketplace at synth-diy.org>

________________________________________________________
This is the Synth-diy mailing list
Submit email to: Synth-diy at synth-diy.org
View archive at: https://synth-diy.org/pipermail/synth-diy/
Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
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From eric.wood74 at gmail.com  Sat Sep  7 21:38:25 2024
From: eric.wood74 at gmail.com (Eric Wood)
Date: Sat, 7 Sep 2024 14:38:25 -0500
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <3E5C73E8-436D-4765-B2E3-C1280C229466@synthcube.com>
References: <3E5C73E8-436D-4765-B2E3-C1280C229466@synthcube.com>
Message-ID: <E9DAF2B8-4F4C-4B1A-8806-2C1275955AF0@gmail.com>

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From tim.parkhurst at gmail.com  Sat Sep  7 21:54:17 2024
From: tim.parkhurst at gmail.com (Tim Parkhurst)
Date: Sat, 7 Sep 2024 12:54:17 -0700
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <PH7PR12MB7188D54BF2A9380AE47D3EC6C89E2@PH7PR12MB7188.namprd12.prod.outlook.com>
References: <PH7PR12MB7188D54BF2A9380AE47D3EC6C89E2@PH7PR12MB7188.namprd12.prod.outlook.com>
Message-ID: <CACDGQT8fppQvDTQ0mAVfefWsM_wsL04pnSM5g5oa4v+Uo5z6bA@mail.gmail.com>

Other firms I've used at work include Send-Cut-Send, and Xometry. SCS is
great for flat panels, or relatively simple bent sheet metal parts, but
their price and delivery are very good.
=============SELF-PROMOTION ALERT===============
I like picking up the occasional side gig doing mechanical design and
drafting, so if you need accurate 3D CAD models and/or production drawings.
Hit me up. I charge $45 an hour (which is actually pretty cheap for this
sort of work), and I have almost 30 years of experience doing mechanical
and electro-mechanical design. I can also do photo-realistic 3D rendering
if you want to evaluate a panel layout or graphic (like the work I did for
Oberheim on the Son Of 4 Voice and the Two Voice Pro), or if you want
images for marketing or web use. You can contact me at

cadguyforhire at gmail.com
==============END SELF-PROMOTION==================


Tim (pimpin' on a Saturday morning) Servo
---
"Imagination is more important than knowledge." - Albert Einstein





On Fri, Sep 6, 2024 at 7:40?AM Dan Snazelle via Synth-diy <
synth-diy at synth-diy.org> wrote:

> Hello All
>
> Feel free to contact me off list if this is too esoteric but I was
> wondering if anyone has contacts in the USA or Canada for places that can
> do runs of custom aluminum boxes even better if they can also do
> powdercoating/etc.
>
>
> All my old contacts circa 5 years ago seem to have gone under.
>
>
> thanks
>
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>
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From declareupdate at gmail.com  Sat Sep  7 22:32:27 2024
From: declareupdate at gmail.com (Chris McDowell)
Date: Sat, 7 Sep 2024 16:32:27 -0400
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <CACDGQT8fppQvDTQ0mAVfefWsM_wsL04pnSM5g5oa4v+Uo5z6bA@mail.gmail.com>
References: <CACDGQT8fppQvDTQ0mAVfefWsM_wsL04pnSM5g5oa4v+Uo5z6bA@mail.gmail.com>
Message-ID: <583A672F-3D2F-4B38-A265-282CD786A09B@gmail.com>

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From brianw at audiobanshee.com  Sun Sep  8 06:16:17 2024
From: brianw at audiobanshee.com (brianw)
Date: Sat, 7 Sep 2024 21:16:17 -0700
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <768A75B5-BCE2-44C5-BE36-D34801379F19@earthlink.net>
References: <CADwb0P1tisD8WR6Q1E-0_KBDC8ksNdVY1FKZYzY4gg7hH7wF6w@mail.gmail.com>
 <9728F780-1B09-4D5C-9B3D-0DB83B1FD079@gmail.com>
 <768A75B5-BCE2-44C5-BE36-D34801379F19@earthlink.net>
Message-ID: <873163BD-36E3-4EDA-8DD5-0B5F85E8A627@audiobanshee.com>

Front Panel Express is great. They'll even let you supply the material and drill or engrave (which I did once when I realized that I needed to add to an initial design). Prices are very reasonable, although you might have to get creative (e.g. choosing anodized panels means that you can engrave lettering without paying for paint, which can get expensive for a lot of letters). I have used them many times when I lived in Seattle and could drive to their shop.

Last time I checked, though, Front Panel Express was not very affordable for making (rack mount) enclosures. I couldn't find a good price at the time. Perhaps their pricing has changed. Seems like you might save a lot of money by sourcing a blank enclosure elsewhere, and then have Front Panel Express drill and engrave to customize for your application.

Brian


On Sep 7, 2024, at 11:59 AM, TERRY SHULTZ wrote:
> Hi Chris,
> 
> We have used Neal Feay in Santa Barbara area https://www.nealfeay.com for our most complex and exotic panels 
> 
> And you guys might want to look at Front Panel Express. I believe their tools are free for design and layout.
> 
> Just my 2 cents.
> 
> Regards,
> 
> Terry
> 
> On Sep 7, 2024, at 1:01?AM, loss wrote:
>> thanks for all the responses. 
>> 
>> At the moment I am trying to do non-hammond style enclosures
>> 
>>  (but getting some pre-drilled powder coated hammond style boxes is always useful too so thanks for that Tim--AND OMG those drill jigs look like such a good idea! def gonna try that)
>> 
>> 
>> 
>> in response to those who sent me aluminum bending places-- do you also use them for powerdercoating and silkscreen? 
>> 
>> It might be too much to ask (or it might not exist these days) but I am dreaming of finding a place I could get them to do metal., powder AND silkscreen (or that new printing process for the graphics.... )
>> 
>> 
>> a man can dream :)
>> 
>> thanks
>> 
>> On Fri, Sep 6, 2024 at 7:40?AM Dan Snazelle wrote:
>>> Hello All
>>> 
>>> Feel free to contact me off list if this is too esoteric but I was wondering if anyone has contacts in the USA or Canada for places that can do runs of custom aluminum boxes even better if they can also do powdercoating/etc.
>>> 
>>> 
>>> All my old contacts circa 5 years ago seem to have gone under. 
>>> 
>>> 
>>> thanks



From rutgervlek at gmail.com  Sun Sep  8 12:34:36 2024
From: rutgervlek at gmail.com (Rutger Vlek)
Date: Sun, 8 Sep 2024 12:34:36 +0200
Subject: [sdiy] Non-linear properties of SSM2040
Message-ID: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>

Dear all,

In the sparse moments between day time job and fatherhood I'm trying to
push forward with an idea I've had for a long time. I'm trying to capture
the variation in favourable non-linear characteristics from well-known
filters (read SSM2040 and Moog Ladder) and implement them in a more modern
topology (read SSI2164). Would also be great to be able to select between
them, while using the same filter core. I'm not necessarily aiming for
perfectly cloning the response of vintage filters, but rather hope to take
inspiration from them and perhaps to discover other pleasant
non-linearities.

I've been approaching this with Spice as well as with mathematical
modelling in Python, using a multi-dimensional Newton-Raphson solver with
the system of equations needed to describe the various filters.

Right now I'm trying to understand the character of the SSM2040, and am a
bit puzzled. I am familiar with the inverting cascaded topology of this
filter. And with the typical math that describes the non-linearities of an
OTA-based filter:
Vout = g * tanh(Vin-Vout).

I have been reading across the internet about the asymmetrical saturation
of this filter, most notably in the application notes for making filters
with the SSI2164: https://www.soundsemiconductor.com/downloads/AN701.pdf.
Based on this information, I had assumed that the tanh only operates in one
direction, something like this:
y = tanh(x)    if x < 0
y =x               if x > 0

However, in Spice, when simulating the internals of the SSM2040 using
Jurgen Haible's schematic (
http://jhaible.com/legacy/tonline_stuff/jh2040.gif), I don't see that
happening. Instead, I see tanh distortion in both directions.

Only when I push the input harder (beyond 1Vpp), I see one side of the
output clipping much sooner than the other. This seems in line with the
effect described in AN701, but is the SSM2040 really driven that hard in
real world applications, and is it really *this* additional effect, on top
of the already present tanh distortion, that explains the SSM2040's
character? And if so... how would one model it mathematically?

Rutger
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From rutgervlek at gmail.com  Sun Sep  8 12:40:16 2024
From: rutgervlek at gmail.com (Rutger Vlek)
Date: Sun, 8 Sep 2024 12:40:16 +0200
Subject: [sdiy] Non-linear properties of SSM2040
In-Reply-To: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
References: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
Message-ID: <CAJ2Txe2CzwVOmhG7=a9ZgidSLx=HnXEiSsUuohxSi=utFFxstg@mail.gmail.com>

By the way, forgot to mention that I dug through our list's history and it
seems Jurgen Haible observed something similar, questioning if the SSM2040
is symmetric after all....
https://synth-diy.org/pipermail/synth-diy/1996-April/035864.html

Also, the clipping effect that I see at higher levels seems much different
between the implementation of Jurgen Haible and that of Rene Schmitz:
https://www.schmitzbits.de/rs2040.html. If it is crucial for the character
of the SSM2040, these two implementations should sound very differently,
unless I'm mistaken?

Finally, I'm hoping that Andrew Simper will chime in, as I love his digital
implementation of the SSM2040! Of course I'm also understanding in case you
cannot share too many details, Andrew :).

Regards,

Rutger

Op zo 8 sep 2024 om 12:34 schreef Rutger Vlek <rutgervlek at gmail.com>:

> Dear all,
>
> In the sparse moments between day time job and fatherhood I'm trying to
> push forward with an idea I've had for a long time. I'm trying to capture
> the variation in favourable non-linear characteristics from well-known
> filters (read SSM2040 and Moog Ladder) and implement them in a more modern
> topology (read SSI2164). Would also be great to be able to select between
> them, while using the same filter core. I'm not necessarily aiming for
> perfectly cloning the response of vintage filters, but rather hope to take
> inspiration from them and perhaps to discover other pleasant
> non-linearities.
>
> I've been approaching this with Spice as well as with mathematical
> modelling in Python, using a multi-dimensional Newton-Raphson solver with
> the system of equations needed to describe the various filters.
>
> Right now I'm trying to understand the character of the SSM2040, and am a
> bit puzzled. I am familiar with the inverting cascaded topology of this
> filter. And with the typical math that describes the non-linearities of an
> OTA-based filter:
> Vout = g * tanh(Vin-Vout).
>
> I have been reading across the internet about the asymmetrical saturation
> of this filter, most notably in the application notes for making filters
> with the SSI2164: https://www.soundsemiconductor.com/downloads/AN701.pdf.
> Based on this information, I had assumed that the tanh only operates in one
> direction, something like this:
> y = tanh(x)    if x < 0
> y =x               if x > 0
>
> However, in Spice, when simulating the internals of the SSM2040 using
> Jurgen Haible's schematic (
> http://jhaible.com/legacy/tonline_stuff/jh2040.gif), I don't see that
> happening. Instead, I see tanh distortion in both directions.
>
> Only when I push the input harder (beyond 1Vpp), I see one side of the
> output clipping much sooner than the other. This seems in line with the
> effect described in AN701, but is the SSM2040 really driven that hard in
> real world applications, and is it really *this* additional effect, on top
> of the already present tanh distortion, that explains the SSM2040's
> character? And if so... how would one model it mathematically?
>
> Rutger
>
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From neil.johnson71 at gmail.com  Sun Sep  8 13:02:05 2024
From: neil.johnson71 at gmail.com (Neil Johnson)
Date: Sun, 8 Sep 2024 12:02:05 +0100
Subject: [sdiy] Cambridge weekend coming up!
Message-ID: <CACZGMxKi2EP4uGtBBd_G1Dkvj+=ZbPsOO6byUedacX6N_3-s2g@mail.gmail.com>

Hi all,

A timely reminder that the Cambridge Synth DIY weekend (27th-29th
September) is fast approaching!  Still time to book a room if you haven't
already:

https://www.synth-diy.uk/

Cheers,
Neil
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From rburnett at richieburnett.co.uk  Sun Sep  8 16:03:30 2024
From: rburnett at richieburnett.co.uk (rburnett at richieburnett.co.uk)
Date: Sun, 08 Sep 2024 15:03:30 +0100
Subject: [sdiy] Non-linear properties of SSM2040
In-Reply-To: <CAJ2Txe2CzwVOmhG7=a9ZgidSLx=HnXEiSsUuohxSi=utFFxstg@mail.gmail.com>
References: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
 <CAJ2Txe2CzwVOmhG7=a9ZgidSLx=HnXEiSsUuohxSi=utFFxstg@mail.gmail.com>
Message-ID: <519749eba2b31fbf456ea3c0379a34f1@richieburnett.co.uk>

Interesting stuff Rutger. And I will be interested to follow the replies 
to this thread.

What are you using to characterise your 2040 filter? Sinewaves, 
impulses, steps, sawtooths...?

-Richie,



On 2024-09-08 11:40, Rutger Vlek via Synth-diy wrote:
> By the way, forgot to mention that I dug through our list's history
> and it seems Jurgen Haible observed something similar, questioning if
> the SSM2040 is symmetric after all....
> 
> https://synth-diy.org/pipermail/synth-diy/1996-April/035864.html
> 
> Also, the clipping effect that I see at higher levels seems much
> different between the implementation of Jurgen Haible and that of Rene
> Schmitz: https://www.schmitzbits.de/rs2040.html. If it is crucial for
> the character of the SSM2040, these two implementations should sound
> very differently, unless I'm mistaken?
> 
> Finally, I'm hoping that Andrew Simper will chime in, as I love his
> digital implementation of the SSM2040! Of course I'm also
> understanding in case you cannot share too many details, Andrew :).
> 
> Regards,
> 
> Rutger
> 
> Op zo 8 sep 2024 om 12:34 schreef Rutger Vlek <rutgervlek at gmail.com>:
> 
>> Dear all,
>> 
>> In the sparse moments between day time job and fatherhood I'm trying
>> to push forward with an idea I've had for a long time. I'm trying to
>> capture the variation in favourable non-linear characteristics from
>> well-known filters (read SSM2040 and Moog Ladder) and implement them
>> in a more modern topology (read SSI2164). Would also be great to be
>> able to select between them, while using the same filter core. I'm
>> not necessarily aiming for perfectly cloning the response of vintage
>> filters, but rather hope to take inspiration from them and perhaps
>> to discover other pleasant non-linearities.
>> 
>> I've been approaching this with Spice as well as with mathematical
>> modelling in Python, using a multi-dimensional Newton-Raphson solver
>> with the system of equations needed to describe the various filters.
>> 
>> Right now I'm trying to understand the character of the SSM2040, and
>> am a bit puzzled. I am familiar with the inverting cascaded topology
>> of this filter. And with the typical math that describes the
>> non-linearities of an OTA-based filter:
>> Vout = g * tanh(Vin-Vout).
>> 
>> I have been reading across the internet about the asymmetrical
>> saturation of this filter, most notably in the application notes for
>> making filters with the SSI2164:
>> https://www.soundsemiconductor.com/downloads/AN701.pdf. Based on
>> this information, I had assumed that the tanh only operates in one
>> direction, something like this:
>> y = tanh(x)    if x < 0
>> y =x               if x > 0
>> 
>> However, in Spice, when simulating the internals of the SSM2040
>> using Jurgen Haible's schematic
>> (http://jhaible.com/legacy/tonline_stuff/jh2040.gif), I don't see
>> that happening. Instead, I see tanh distortion in both directions.
>> 
>> Only when I push the input harder (beyond 1Vpp), I see one side of
>> the output clipping much sooner than the other. This seems in line
>> with the effect described in AN701, but is the SSM2040 really driven
>> that hard in real world applications, and is it really *this*
>> additional effect, on top of the already present tanh distortion,
>> that explains the SSM2040's character? And if so... how would one
>> model it mathematically?
>> 
>> Rutger
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: 
> https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org

From synth at schmitzbits.de  Sun Sep  8 16:39:27 2024
From: synth at schmitzbits.de (=?UTF-8?Q?Ren=C3=A9_Schmitz?=)
Date: Sun, 8 Sep 2024 16:39:27 +0200
Subject: [sdiy] Non-linear properties of SSM2040
In-Reply-To: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
References: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
Message-ID: <2b98c212-3d47-4490-a668-a26fe513628b@schmitzbits.de>

Hi Rutger and all,


The TANH comes from the input side, i.e. the long tail pair transistors, 
this is more or less symmetric as one would expect.

(If you ignore minor effects such as the different Vce voltages, Vbe 
matching, source resistances etc.)


For a single stage:

The asymmetry comes from the output of the one-mirror OTA. It can't sink 
past -0.6V (The collector of the output transistor can't go lower than 
it's emitter voltage, with the bases near GND thats about -0.6V).

Thus you see clipping at -0.6V.

It really only makes a difference if you're *not* summing the current 
into a virtual ground. As was done in the 2040 of course, which uses 
emitter followers.

(But you can run the 2040 gain stage into an opamp integrator and do not 
get any of the clipping at all.)


BTW the 2164 also has voltage compliance limits for its output current 
(albeit different).

So you can run the 2164 into an "open" load, and get extra 
nonlinearities. Thats mentioned in AN701.


If you cascade several inverting 2040 stages, then at the output you get 
(more or less) symmetric clipping because you alternately treat the 
positive and negative input swings at consecutive stages.

I think this was what JH was talking about. But also look at a single 
stage to understand what the root behaviour is.



Best,

 ?Ren?




Am 08.09.2024 um 12:34 schrieb Rutger Vlek via Synth-diy:
> Dear all,
>
> In the sparse moments between day time job and fatherhood I'm trying 
> to push forward with an idea I've had for a long time. I'm trying to 
> capture the variation in favourable non-linear characteristics from 
> well-known filters (read SSM2040 and Moog Ladder) and implement them 
> in a more modern topology (read SSI2164). Would also be great to be 
> able to select between them,?while using the same filter core. I'm not 
> necessarily?aiming for perfectly cloning the response of vintage 
> filters, but rather hope to take inspiration from them and perhaps to 
> discover?other pleasant non-linearities.
>
> I've been approaching this with Spice as well as with mathematical 
> modelling in Python, using a multi-dimensional Newton-Raphson solver 
> with the system of equations needed to describe the various filters.
>
> Right now I'm trying to understand the character of the SSM2040, and 
> am a bit puzzled. I am familiar with the inverting cascaded topology 
> of this filter. And with the typical math that describes the 
> non-linearities of an OTA-based filter:
> Vout = g * tanh(Vin-Vout).
>
> I have been reading across the internet about the asymmetrical 
> saturation of this filter, most notably in the application notes for 
> making filters with the SSI2164: 
> https://www.soundsemiconductor.com/downloads/AN701.pdf. Based on this 
> information, I had assumed that the tanh only operates in one 
> direction, something like this:
> y = tanh(x)? ? if x < 0
> y =x? ? ? ? ? ? ? ?if x > 0
>
> However, in Spice, when simulating the internals of the SSM2040 using 
> Jurgen Haible's?schematic 
> (http://jhaible.com/legacy/tonline_stuff/jh2040.gif), I don't see that 
> happening. Instead, I see tanh distortion in both directions.
>
> Only when I push the input harder (beyond 1Vpp), I see one side of the 
> output clipping much sooner than the other. This seems in line with 
> the effect described in AN701, but is the SSM2040 really driven that 
> hard in real world applications, and is it really *this* additional 
> effect, on top of the already present tanh distortion, that explains 
> the SSM2040's character? And if so... how would one model it 
> mathematically?
>
> Rutger
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org

-- 
--
synth at schmitzbits.de
http://schmitzbits.de


From rutgervlek at gmail.com  Sun Sep  8 17:01:28 2024
From: rutgervlek at gmail.com (Rutger Vlek)
Date: Sun, 8 Sep 2024 17:01:28 +0200
Subject: [sdiy] Non-linear properties of SSM2040
In-Reply-To: <2b98c212-3d47-4490-a668-a26fe513628b@schmitzbits.de>
References: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
 <2b98c212-3d47-4490-a668-a26fe513628b@schmitzbits.de>
Message-ID: <CAJ2Txe2uuuY_JMiQiQtzXkBCGnrL1OZV5sbiNZkPRvZd9TWMdg@mail.gmail.com>

@Richie Burnett <rburnett at richieburnett.co.uk> thanks! I have found Spice
to be cumbersome for more advanced data analysis, so resorted to Python for
most of it. There I am studying non linearities using saw, ramp (inverted
saw) and sine test signals. The latter I use mostly for spectral analysis,
while the first are also informative about time domain effects. I also
created the option to put out wat files so that I can audition them. Some
effects that were impressive in the time domain where irrelevant when
listening, and (more importantly!) vice versa. I had to make a bad
prototype to remind me of this... What resembled the time domain of a Moog
filter did not sound like one. As soon as I studied the spectral domain
data I understood why.

The spectral effects on a sawtooth pushed through a non linear filter,
without any resonance are impressive by themselves by the way. I never knew
the effect of an analogue filter could be this substantial.

@Ren? Schmitz <synth at schmitzbits.de> Thanks for the explanation! It
confirms what I already suspected. The non linear effects are a combination
of TanH and something else. I have the feeling your answer also implies
that the latter effect is important for the character of the ssm2040.

Best,

Rutger

Op zo 8 sep 2024 16:39 schreef Ren? Schmitz <synth at schmitzbits.de>:

> Hi Rutger and all,
>
>
> The TANH comes from the input side, i.e. the long tail pair transistors,
> this is more or less symmetric as one would expect.
>
> (If you ignore minor effects such as the different Vce voltages, Vbe
> matching, source resistances etc.)
>
>
> For a single stage:
>
> The asymmetry comes from the output of the one-mirror OTA. It can't sink
> past -0.6V (The collector of the output transistor can't go lower than
> it's emitter voltage, with the bases near GND thats about -0.6V).
>
> Thus you see clipping at -0.6V.
>
> It really only makes a difference if you're *not* summing the current
> into a virtual ground. As was done in the 2040 of course, which uses
> emitter followers.
>
> (But you can run the 2040 gain stage into an opamp integrator and do not
> get any of the clipping at all.)
>
>
> BTW the 2164 also has voltage compliance limits for its output current
> (albeit different).
>
> So you can run the 2164 into an "open" load, and get extra
> nonlinearities. Thats mentioned in AN701.
>
>
> If you cascade several inverting 2040 stages, then at the output you get
> (more or less) symmetric clipping because you alternately treat the
> positive and negative input swings at consecutive stages.
>
> I think this was what JH was talking about. But also look at a single
> stage to understand what the root behaviour is.
>
>
>
> Best,
>
>   Ren?
>
>
>
>
> Am 08.09.2024 um 12:34 schrieb Rutger Vlek via Synth-diy:
> > Dear all,
> >
> > In the sparse moments between day time job and fatherhood I'm trying
> > to push forward with an idea I've had for a long time. I'm trying to
> > capture the variation in favourable non-linear characteristics from
> > well-known filters (read SSM2040 and Moog Ladder) and implement them
> > in a more modern topology (read SSI2164). Would also be great to be
> > able to select between them, while using the same filter core. I'm not
> > necessarily aiming for perfectly cloning the response of vintage
> > filters, but rather hope to take inspiration from them and perhaps to
> > discover other pleasant non-linearities.
> >
> > I've been approaching this with Spice as well as with mathematical
> > modelling in Python, using a multi-dimensional Newton-Raphson solver
> > with the system of equations needed to describe the various filters.
> >
> > Right now I'm trying to understand the character of the SSM2040, and
> > am a bit puzzled. I am familiar with the inverting cascaded topology
> > of this filter. And with the typical math that describes the
> > non-linearities of an OTA-based filter:
> > Vout = g * tanh(Vin-Vout).
> >
> > I have been reading across the internet about the asymmetrical
> > saturation of this filter, most notably in the application notes for
> > making filters with the SSI2164:
> > https://www.soundsemiconductor.com/downloads/AN701.pdf. Based on this
> > information, I had assumed that the tanh only operates in one
> > direction, something like this:
> > y = tanh(x)    if x < 0
> > y =x               if x > 0
> >
> > However, in Spice, when simulating the internals of the SSM2040 using
> > Jurgen Haible's schematic
> > (http://jhaible.com/legacy/tonline_stuff/jh2040.gif), I don't see that
> > happening. Instead, I see tanh distortion in both directions.
> >
> > Only when I push the input harder (beyond 1Vpp), I see one side of the
> > output clipping much sooner than the other. This seems in line with
> > the effect described in AN701, but is the SSM2040 really driven that
> > hard in real world applications, and is it really *this* additional
> > effect, on top of the already present tanh distortion, that explains
> > the SSM2040's character? And if so... how would one model it
> > mathematically?
> >
> > Rutger
> >
> > ________________________________________________________
> > This is the Synth-diy mailing list
> > Submit email to: Synth-diy at synth-diy.org
> > View archive at: https://synth-diy.org/pipermail/synth-diy/
> > Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> > Selling or trading? Use marketplace at synth-diy.org
>
> --
> --
> synth at schmitzbits.de
> http://schmitzbits.de
>
>
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From rburnett at richieburnett.co.uk  Sun Sep  8 20:02:52 2024
From: rburnett at richieburnett.co.uk (rburnett at richieburnett.co.uk)
Date: Sun, 08 Sep 2024 19:02:52 +0100
Subject: [sdiy] Non-linear properties of SSM2040
In-Reply-To: <CAJ2Txe2uuuY_JMiQiQtzXkBCGnrL1OZV5sbiNZkPRvZd9TWMdg@mail.gmail.com>
References: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
 <2b98c212-3d47-4490-a668-a26fe513628b@schmitzbits.de>
 <CAJ2Txe2uuuY_JMiQiQtzXkBCGnrL1OZV5sbiNZkPRvZd9TWMdg@mail.gmail.com>
Message-ID: <10e166aae8e33acaeedcd51f787f3aa4@richieburnett.co.uk>

> The spectral effects on a sawtooth pushed through a non linear filter,
> without any resonance are impressive by themselves by the way. I never
> knew the effect of an analogue filter could be this substantial.

Yes, I found that the effects of non-linearities were greatest for the 
"zero resonance" case when I looked at the TB-303 filter in some detail. 
  When you turn up the resonance control the global negative feedback 
applied around the filter stages does a good job of linearising the 
filter.  So, it was actually easier to nail the high-resonance sound 
with a digital model than it was to nail the zero-resonance sound!

-Richie,

From kmkennedy at gmail.com  Sun Sep  8 21:08:22 2024
From: kmkennedy at gmail.com (Kylee Kennedy)
Date: Sun, 8 Sep 2024 12:08:22 -0700
Subject: [sdiy] Custom Aluminum Shops?
In-Reply-To: <PH7PR12MB7188D54BF2A9380AE47D3EC6C89E2@PH7PR12MB7188.namprd12.prod.outlook.com>
References: <PH7PR12MB7188D54BF2A9380AE47D3EC6C89E2@PH7PR12MB7188.namprd12.prod.outlook.com>
Message-ID: <CADD61nUscGFY9EMCGEmj6q+95O2Zn9dd809zRMGdB5ft2wrY2g@mail.gmail.com>

I've heard good things about this one:
https://hmetal.com/
Hamilton Metalcraft - based in Pasadena, CA and I know they do the Serge
boat cases for Prism Circuits.
https://prismcircuits.net/

- Kylee

On Fri, Sep 6, 2024 at 7:38?AM Dan Snazelle via Synth-diy <
synth-diy at synth-diy.org> wrote:

> Hello All
>
> Feel free to contact me off list if this is too esoteric but I was
> wondering if anyone has contacts in the USA or Canada for places that can
> do runs of custom aluminum boxes even better if they can also do
> powdercoating/etc.
>
>
> All my old contacts circa 5 years ago seem to have gone under.
>
>
> thanks
>
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org
>
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From admin at bugbrand.co.uk  Sun Sep  8 21:57:45 2024
From: admin at bugbrand.co.uk (Tom Bugs)
Date: Sun, 8 Sep 2024 20:57:45 +0100
Subject: [sdiy] Non-linear properties of SSM2040
In-Reply-To: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
References: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
Message-ID: <f04ba048-ea4a-4a42-be6f-cc44f72cfdf3@bugbrand.co.uk>

I have little technical to offer, but wondered whether you were aware 
that SSI have the SSI2040 with a pretty detailed datasheet (updated Mar 
'23) - https://www.soundsemiconductor.com/downloads/ssi2140datasheet.pdf

Curious what might be gained from trying to implement it with the 2164 
instead?

Tom

On 08/09/2024 11:34, Rutger Vlek via Synth-diy wrote:
> Dear all,
>
> In the sparse moments between day time job and fatherhood I'm trying 
> to push forward with an idea I've had for a long time. I'm trying to 
> capture the variation in favourable non-linear characteristics from 
> well-known filters (read SSM2040 and Moog Ladder) and implement them 
> in a more modern topology (read SSI2164). Would also be great to be 
> able to select between them,?while using the same filter core. I'm not 
> necessarily?aiming for perfectly cloning the response of vintage 
> filters, but rather hope to take inspiration from them and perhaps to 
> discover?other pleasant non-linearities.
>
> I've been approaching this with Spice as well as with mathematical 
> modelling in Python, using a multi-dimensional Newton-Raphson solver 
> with the system of equations needed to describe the various filters.
>
> Right now I'm trying to understand the character of the SSM2040, and 
> am a bit puzzled. I am familiar with the inverting cascaded topology 
> of this filter. And with the typical math that describes the 
> non-linearities of an OTA-based filter:
> Vout = g * tanh(Vin-Vout).
>
> I have been reading across the internet about the asymmetrical 
> saturation of this filter, most notably in the application notes for 
> making filters with the SSI2164: 
> https://www.soundsemiconductor.com/downloads/AN701.pdf. Based on this 
> information, I had assumed that the tanh only operates in one 
> direction, something like this:
> y = tanh(x)? ? if x < 0
> y =x? ? ? ? ? ? ? ?if x > 0
>
> However, in Spice, when simulating the internals of the SSM2040 using 
> Jurgen Haible's?schematic 
> (http://jhaible.com/legacy/tonline_stuff/jh2040.gif), I don't see that 
> happening. Instead, I see tanh distortion in both directions.
>
> Only when I push the input harder (beyond 1Vpp), I see one side of the 
> output clipping much sooner than the other. This seems in line with 
> the effect described in AN701, but is the SSM2040 really driven that 
> hard in real world applications, and is it really *this* additional 
> effect, on top of the already present tanh distortion, that explains 
> the SSM2040's character? And if so... how would one model it 
> mathematically?
>
> Rutger
>
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
> Selling or trading? Use marketplace at synth-diy.org

-- 
BugBrand LTD
UK company No. 07199808
VAT No. GB 988 2629 57
1 Ninetree Hill
BRISTOL BS1 3SB
United Kingdom
www.bugbrand.co.uk


From synth at schmitzbits.de  Mon Sep  9 01:00:00 2024
From: synth at schmitzbits.de (=?UTF-8?Q?Ren=C3=A9_Schmitz?=)
Date: Mon, 9 Sep 2024 01:00:00 +0200
Subject: [sdiy] Non-linear properties of SSM2040
In-Reply-To: <CAJ2Txe2uuuY_JMiQiQtzXkBCGnrL1OZV5sbiNZkPRvZd9TWMdg@mail.gmail.com>
References: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
 <2b98c212-3d47-4490-a668-a26fe513628b@schmitzbits.de>
 <CAJ2Txe2uuuY_JMiQiQtzXkBCGnrL1OZV5sbiNZkPRvZd9TWMdg@mail.gmail.com>
Message-ID: <8bfc311b-e543-445a-95e9-4af194b048d8@schmitzbits.de>

On 08.09.2024 17:01, Rutger Vlek wrote:
> @Richie Burnett <mailto:rburnett at richieburnett.co.uk>?thanks! I have 
> found Spice to be cumbersome for more advanced data analysis, so 
> resorted to Python for most of it. There I am studying non linearities 
> using saw, ramp (inverted saw) and sine test signals. The latter I use 
> mostly for spectral analysis, while the first are also informative 
> about time domain effects. I also created the option to put out wat 
> files so that I can audition them. Some effects that were impressive 
> in the time domain where irrelevant when listening, and (more 
> importantly!) vice versa. I had to make a bad prototype to remind me 
> of this... What resembled the time domain of a Moog filter did not 
> sound like one. As soon as I studied the spectral domain data I 
> understood why.
>
> The spectral effects on a sawtooth pushed through a non linear filter, 
> without any resonance are impressive by themselves by the way. I never 
> knew the effect of an analogue filter could be this substantial.
>
> @Ren? Schmitz <mailto:synth at schmitzbits.de>?Thanks for the 
> explanation! It confirms what I already suspected. The non linear 
> effects are a combination of TanH and something else. I have the 
> feeling your answer also implies that the latter effect is important 
> for the character of the ssm2040.


The tanh works on the input voltage to current translation, and the 
clipping is on the cap side, so that's after the current was integrated 
back to a voltage .

Hence it's not something you can lump together into one non linearity. 
You only get so far if you look at it statically.

How fast the cap is charged to -0.6V depends of course on the control 
current, the size of the cap, and how long it is applied. Plus the 
initial conditions.

The input attenuation at the bases of the long tail pair together with 
the input amplitude determine to what degree the tanh is actually driven.

If it's below 25mV you don't have a significant contribution from it, 
pretty linear.

(With the 10k/200 divider common to JHs and mine the 2040 cells are 
driven quite beefy, for +/-2.5V input, resulting in +/-50mV after the 
attenuation.)

And there is also a feedback loop that works to get things back into 
balance at the bases, i.e. to reduce deltaVbe.

Then we could ask what effect does the darlington emitter follower with 
it's two Vbes have?

Spoiler alert, it shifts the whole waveform voltage at the cap upwards, 
away from the clipping.

Theoretically you could add more Vbe drops and steer it clear of the 
clipping zone (but who wants that...).


There surely is a lot going on in that simple circuit.


Best,
 ?Ren?



--
synth at schmitzbits.de
http://schmitzbits.de
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From andy at cytomic.com  Mon Sep  9 02:43:43 2024
From: andy at cytomic.com (Andrew Simper)
Date: Mon, 9 Sep 2024 08:43:43 +0800
Subject: [sdiy] Non-linear properties of SSM2040
In-Reply-To: <2b98c212-3d47-4490-a668-a26fe513628b@schmitzbits.de>
References: <CAJ2Txe31jjVO8WMPynr9++QSGrpooksV6bkNk_AdO760gDB4aQ@mail.gmail.com>
 <2b98c212-3d47-4490-a668-a26fe513628b@schmitzbits.de>
Message-ID: <CAAxOnzYoGvQM=Tpy=vida+SgQSZViU_9O0D9=SzRkgHOao+kMQ@mail.gmail.com>

I've modelled the SSM2040 in detail, it's available as a filter module for
the virtual eurorack VCV software: https://cytomic.com/vcv-rack-modules/
and I've done a comparison video matching against the SSI2140 datasheet
version implemented in the LA67 Maca module:
https://www.youtube.com/watch?v=wVYYDvAXEjY

Ren?'s summary is great, but I'll add a few more details inline below:

On Sun, 8 Sept 2024 at 22:39, Ren? Schmitz <synth at schmitzbits.de> wrote:

> Hi Rutger and all,
>
>
> The TANH comes from the input side, i.e. the long tail pair transistors,
> this is more or less symmetric as one would expect.
>
> (If you ignore minor effects such as the different Vce voltages, Vbe
> matching, source resistances etc.)
>
>
> For a single stage:
>
> The asymmetry comes from the output of the one-mirror OTA. It can't sink
> past -0.6V (The collector of the output transistor can't go lower than
> it's emitter voltage, with the bases near GND thats about -0.6V).
>
> Thus you see clipping at -0.6V.
>
> It really only makes a difference if you're *not* summing the current
> into a virtual ground. As was done in the 2040 of course, which uses
> emitter followers.
>
> (But you can run the 2040 gain stage into an opamp integrator and do not
> get any of the clipping at all.)
>

The main non-tanh part of the input is due to the finite beta of the input
differential pair.

The "classic" buffer (non-virtual ground) adds some voltage offset (around
-1.05V depending on the BJT used) to the signal, which is then fed back to
the negative input of the same stage, which raises the input by the same
amount, and which gives the circuit extra headroom of around a negative
excursion of around -1.65V before clipping. This will leave positive
excursions intact for the first stage, but since each stage inverts then
this positive waveform will then become negative and get clipped off at the
next stage, which is repeated another two times. This clipping is done
without buffering from the low pass capacitor by the negative input BJT,
but also a near positive voltage rail clipping in a similar manner from the
current mirror. These two unbuffered "diode" clippers drain the low pass
capacitor of current before that stage's voltage is buffered - and the
buffer also adds a little drive.



> BTW the 2164 also has voltage compliance limits for its output current
> (albeit different).
>
> So you can run the 2164 into an "open" load, and get extra
> nonlinearities. Thats mentioned in AN701.
>
>
> If you cascade several inverting 2040 stages, then at the output you get
> (more or less) symmetric clipping because you alternately treat the
> positive and negative input swings at consecutive stages.
>

Yes, it's not quite symmetric since there is a one pole worth of low
passing combined with the flipped clipping, but when the cutoff is wide
open it becomes effectively symmetric for audio rate signals.



>
> I think this was what JH was talking about. But also look at a single
> stage to understand what the root behaviour is.
>
>
>
> Best,
>
>   Ren?
>
>
Thanks for the rundown Ren?.

Andy



>
>
>
> Am 08.09.2024 um 12:34 schrieb Rutger Vlek via Synth-diy:
> > Dear all,
> >
> > In the sparse moments between day time job and fatherhood I'm trying
> > to push forward with an idea I've had for a long time. I'm trying to
> > capture the variation in favourable non-linear characteristics from
> > well-known filters (read SSM2040 and Moog Ladder) and implement them
> > in a more modern topology (read SSI2164). Would also be great to be
> > able to select between them, while using the same filter core. I'm not
> > necessarily aiming for perfectly cloning the response of vintage
> > filters, but rather hope to take inspiration from them and perhaps to
> > discover other pleasant non-linearities.
> >
> > I've been approaching this with Spice as well as with mathematical
> > modelling in Python, using a multi-dimensional Newton-Raphson solver
> > with the system of equations needed to describe the various filters.
> >
> > Right now I'm trying to understand the character of the SSM2040, and
> > am a bit puzzled. I am familiar with the inverting cascaded topology
> > of this filter. And with the typical math that describes the
> > non-linearities of an OTA-based filter:
> > Vout = g * tanh(Vin-Vout).
> >
> > I have been reading across the internet about the asymmetrical
> > saturation of this filter, most notably in the application notes for
> > making filters with the SSI2164:
> > https://www.soundsemiconductor.com/downloads/AN701.pdf. Based on this
> > information, I had assumed that the tanh only operates in one
> > direction, something like this:
> > y = tanh(x)    if x < 0
> > y =x               if x > 0
> >
> > However, in Spice, when simulating the internals of the SSM2040 using
> > Jurgen Haible's schematic
> > (http://jhaible.com/legacy/tonline_stuff/jh2040.gif), I don't see that
> > happening. Instead, I see tanh distortion in both directions.
> >
> > Only when I push the input harder (beyond 1Vpp), I see one side of the
> > output clipping much sooner than the other. This seems in line with
> > the effect described in AN701, but is the SSM2040 really driven that
> > hard in real world applications, and is it really *this* additional
> > effect, on top of the already present tanh distortion, that explains
> > the SSM2040's character? And if so... how would one model it
> > mathematically?
> >
> > Rutger
> >
> > ________________________________________________________
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> --
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>
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