Homebrew_PCBs

> How are those tiny metal cilinder named?i`m talking about the one
> used to connect top layer to bottom layer.

----- Original Message -----
From: "preda mihai" <myke_oltcit@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, August 16, 2004 10:17 AM
Subject: [Homebrew_PCBs] double layer question


> How are those tiny metal cilinder named?i`m talking about the one
> used to connect top layer to bottom layer.

Eyelets?

Leon

>How are those tiny metal cilinder named?i`m talking about the one
>used to connect top layer to bottom layer.

> ----- Original Message -----
> From: "preda mihai" <myke_oltcit@y...>
> To: <Homebrew_PCBs@yahoogroups.com>
> Sent: Monday, August 16, 2004 10:17 AM
> Subject: [Homebrew_PCBs] double layer question
>
>
> > How are those tiny metal cilinder named?i`m talking about the one
> > used to connect top layer to bottom layer.
>
> Eyelets?

> has one of you ever tried making a multi-position switch directly on the
> PCB like most handheld meters have?

> I can't gold plate it (yet).
> I think tinning would do for now.
>
> I think of using a M6 screw as axis, just a washer on each side to make a
> bearing of a hole in the PCB. Then take a piece of FR4 and make the "wiper"
> with contacts of thin sheetmetal. The M6 screw would fit into a knob on the
> front panel. The "snap" action could be achieved by drilling holes in the
> PCB and letting some spring catch them.
>
> What do you think of that? stupid idea?

> It seems i can't get rotrary switches with enough positions.

> Would be nice to be able to just make them how i want.
> After all it works in meters...

> tell me what you thik about that.

>
> What are you switching? How many positions do you really _need_? Have
> you
> noticed that rotary switches are in large part going away, or at least
> they
> have been since the fifties? There's a reason for that. Feel free to
> take
> this over to Electronics101 if we get too far off the topic for in here.
>

> > What are you switching? How many positions do you really _need_? Have
> > you noticed that rotary switches are in large part going away, or at
> > least they have been since the fifties? There's a reason for that. Feel
> > free to take this over to Electronics101 if we get too far off the topic
> > for in here.

> I need 2*10 positions, and can only get 2*6 or 1*12.

> For selecting cell count on a battery charger (no current at all).
> Almost all handheld meters i've ever seen use rotary switches, and all i
> took apart had "custom" printed contacts. Oh, yes, there was one rotten
> piece of bad engineering that had four buttons instead. The damn thing had
> dozens of design flaws, like blowing up each time you pulled the current
> plug....
>
> I could try to pull some mechanical stunt and stack 2 1*12 switches.
> I don't know if that would be possibe with the switches i can get.
> But then, one switch for 2.50eur is not exactly cheap, not speaking of 2...

> I need 2*10 positions, and can only get 2*6 or 1*12.
> For selecting cell count on a battery charger (no current at all).
> Almost all handheld meters i've ever seen use rotary switches, and

> took
> apart had "custom" printed contacts. Oh, yes, there was one rotten

> of bad engineering
> that had four buttons instead. The damn thing had dozens of design

> like blowing up
> each time you pulled the current plug....
>
> I could try to pull some mechanical stunt and stack 2 1*12 switches.
> I don't know if that would be possibe with the switches i can get.
> But then, one switch for 2.50eur is not exactly cheap, not speaking

> Hi,
>
>
> has one of you ever tried making a multi-position
> switch directly on the
> PCB like most handheld meters have?

> I can't gold plate it (yet).
> I think tinning would do for now.

>
> I think of using a M6 screw as axis, just a washer
> on each side to make a
> bearing
> of a hole in the PCB. Then take a piece of FR4 and
> make the "wiper" with
> contacts
> of thin sheetmetal.

> The M6 screw would fit into a knob on the front
> panel.
> The "snap" action could be achieved by drilling
> holes in the PCB and
> letting
> some spring catch them.

>
> What do you think of that? stupid idea?

>
> It seems i can't get rotrary switches with enough
> positions.
> Would be nice to be able to just make them how i
> want.
> After all it works in meters...

>
> tell me what you thik about that.

>
> ST
>
>
>
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>

>
>
> Be sure to visit the group home and check for new
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>
>
> Homebrew_PCBs-unsubscribe@yahoogroups.com
>
>
>
>

> One could also use optocouplers and a mylar disk...
> bit it gets spendy.

----- Original Message -----
From: "Roy J. Tellason" <rtellason@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Tuesday, August 31, 2004 12:43 AM
Subject: Re: [Homebrew_PCBs] homebrew rotary multi-position switch


> On Monday 30 August 2004 07:29 pm, ron amundson wrote:
>
> > One could also use optocouplers and a mylar disk...
> > bit it gets spendy.
>
> Not necessarily. I have a couple of motors equipped with such encoders.
And
> you have two of them in any given mouse that's out there -- it shouldn't
be
> too hard to adapt that technology to be used with a knob and a shaft,
though
> a good bit of weight behind the panel gives it a better feel.
>
> This sort of thing was actually used, in a z80-based system to control
most
> all functions on the Moog Source -- you had what was basically a membrane
> panel, where you selected what function you wanted to mess with, you had
a
> couple or three digits of LED display to tell you what the current value
was,
> and you had one big knob to fiddle with it.

Electro-mechanical encoders are quite cheap, they are made by ALPS and
Bourne. One of those with a small MCU and a display will do what you want.

Leon

> ----- Original Message -----
> From: "Roy J. Tellason" <rtellason@...>
> To: <Homebrew_PCBs@yahoogroups.com>
> Sent: Tuesday, August 31, 2004 12:43 AM
> Subject: Re: [Homebrew_PCBs] homebrew rotary
> multi-position switch
>
>
> > On Monday 30 August 2004 07:29 pm, ron amundson
> wrote:
> >
> > > One could also use optocouplers and a mylar
> disk...
> > > bit it gets spendy.
> >
> > Not necessarily. I have a couple of motors
> equipped with such encoders.
> And
> > you have two of them in any given mouse that's out
> there -- it shouldn't
> be
> > too hard to adapt that technology to be used with
> a knob and a shaft,
> though
> > a good bit of weight behind the panel gives it a
> better feel.
> >
> > This sort of thing was actually used, in a
> z80-based system to control
> most
> > all functions on the Moog Source -- you had what
> was basically a membrane
> > panel, where you selected what function you
> wanted to mess with, you had
> a
> > couple or three digits of LED display to tell you
> what the current value
> was,
> > and you had one big knob to fiddle with it.
>
> Electro-mechanical encoders are quite cheap, they
> are made by ALPS and
> Bourne. One of those with a small MCU and a display
> will do what you want.
>
> Leon
>

> So what I gather, is a guy could put a good sized weight on the shaft to
> create inertia and give a perception of quality, then use optical
> interrupters to capture disc position?

> I've looked at the mechanical rotary encoders in the past, but even in
> volume they were a couple bucks. The idea of using oprtical is quite
> interesting. I'd completely forgotten that is the basic mouse concept.

> All one would need to do, is add some type of position encoding to the mouse
> wheel, and one would be all set.

> Hi,
>
>
> has one of you ever tried making a multi-position switch directly

> PCB like most handheld meters have?
> I can't gold plate it (yet).
> I think tinning would do for now.
>
> I think of using a M6 screw as axis, just a washer on each side to

> bearing
> of a hole in the PCB. Then take a piece of FR4 and make the "wiper"

> contacts
> of thin sheetmetal.
> The M6 screw would fit into a knob on the front panel.
> The "snap" action could be achieved by drilling holes in the PCB

> letting
> some spring catch them.
>
> What do you think of that? stupid idea?
>
> It seems i can't get rotrary switches with enough positions.
> Would be nice to be able to just make them how i want.
> After all it works in meters...
>
> tell me what you thik about that.
>
> ST

> > All one would need to do, is add some type of
> position encoding to the mouse
> > wheel, and one would be all set.
>
> Nah, that'll all be handled in the software. As
> would the resolution, for
> that matter.

>
> Could you elaborate as to how..... Especially in a
> power down condition where upon one could loose track.
> I take it, there is some trick, as many devices, use
> relative rather than absolute positioning. WIthout a
> home position to index off of, it would seem one could
> loose the position of the pointer if it were turned
> and power was off.... Or is it interrupt driven such
> that the micro stays alive and wakes up should the
> shaft be turned???
>
> Ron

> Electro-mechanical encoders are quite cheap, they are made by ALPS and
> Bourne. One of those with a small MCU and a display will do what you
> want.
>
> Leon

>
> So what I gather, is a guy could put a good sized
> weight on the shaft to create inertia and give a
> perception of quality, then use optical interrupters
> to capture disc position?

>> > All one would need to do, is add some type of
>> position encoding to the mouse
>> > wheel, and one would be all set.
>>
>> Nah, that'll all be handled in the software. As
>> would the resolution, for
>> that matter.
>
> Could you elaborate as to how..... Especially in a
> power down condition where upon one could loose track.
> I take it, there is some trick, as many devices, use
> relative rather than absolute positioning. WIthout a
> home position to index off of, it would seem one could
> loose the position of the pointer if it were turned
> and power was off.... Or is it interrupt driven such
> that the micro stays alive and wakes up should the
> shaft be turned???
>
> Ron
>

> Could you use multiplexers? That would be more reliable and could
> have as many switches as you want. Mike
>

>
> >
> > What are you switching? How many positions do you really

> > you
> > noticed that rotary switches are in large part going away, or at

> > they
> > have been since the fifties? There's a reason for that. Feel

> > take
> > this over to Electronics101 if we get too far off the topic for

> >
>
> I need 2*10 positions, and can only get 2*6 or 1*12.
> For selecting cell count on a battery charger (no current at all).
> Almost all handheld meters i've ever seen use rotary switches, and

> took
> apart had "custom" printed contacts. Oh, yes, there was one rotten

> of bad engineering
> that had four buttons instead. The damn thing had dozens of design

> like blowing up
> each time you pulled the current plug....
>
> I could try to pull some mechanical stunt and stack 2 1*12 switches.
> I don't know if that would be possibe with the switches i can get.
> But then, one switch for 2.50eur is not exactly cheap, not speaking

>
> ST

>"cybermace5" <cybermace5@y...> wrote:
> Would be nice to have a couple more details on the circuit this is
> going to be connected to.
>
> Are you changing a resistance? Could you use a potentiometer and

> work out some kind of mechanical detent? Why do you need a dual-pole
> switch? Have you looked at analog multiplexer chips? Digital
> potentiometer chips? Don't reject them without looking at them, they
> are not all expensive. A 16:1 analog mux/demux CD74HCT4067 costs 90
> cents in DIP, 48 cents in SOIC. Two of those give you your dual-pole
> circuit if you need it. They accept a simple 4-bit input to select
> which output goes where. You could provide that input with a
> 16-position hex switch, or a 4-bit counter (rollover at 12) operated
> by pushbuttons. Another 50-cent 74HC154 4:16 decoder could give you

> LED feedback showing which output is selected.
>
> It would be neat to have 12 LEDs surrounding a single central
> pushbutton which increments the LED position.
>
> Or maybe you could just go for a rotary switch with fewer positions,
> like 6. Then you use a dual-pole switch to choose between high range
> and low range. Though even 6-position dual-pole rotaries are all

> expensive unless you get lucky in surplus stores.
>
> As for rolling your own? It'll just have to be trial and error.

> > > All one would need to do, is add some type of position encoding to the
> > > mouse wheel, and one would be all set.

> > Nah, that'll all be handled in the software. As would the resolution,
> > for that matter.

> Could you elaborate as to how..... Especially in a power down condition
> where upon one could loose track.

> I take it, there is some trick, as many devices, use relative rather than
> absolute positioning.

> WIthout a home position to index off of, it would seem one could loose the
> position of the pointer if it were turned and power was off.... Or is it
> interrupt driven such that the micro stays alive and wakes up should the
> shaft be turned???

> > Could you elaborate as to how..... Especially in a
> > power down condition where upon one could loose track.
> > I take it, there is some trick, as many devices, use
> > relative rather than absolute positioning. WIthout a
> > home position to index off of, it would seem one could
> > loose the position of the pointer if it were turned
> > and power was off.... Or is it interrupt driven such
> > that the micro stays alive and wakes up should the
> > shaft be turned???
> >
> > Ron
>
> Maybe do like was already stated earlier and just use LEDs around the
> dial to indicate position. Then don't put any position indicators on
> the dial itself. Then when you turn the unit on, you could have it
> start in the "home" position no matter how much the dial itself has
> moved while off.

> Or you could use a bunch of reed switches mounted in a circle and a
> magnet mounted to a disc on the shaft, but I'm sure that would be
> pretty pricy.

> I've heard that green LEDs can act as photodetectors. They are cheap
> if you could get them to work. Then just put a bunch in a circle a
> detectors and one on a disc on the shaft as an emitter. Anybody have
> any luck using LEDs as detectors?

> Another option is the 0-9 thumbwheel switches. I see these in ALL the
> surplus places these days, and they ARE a rotary switch, just a 90
> degree orientation change. Most are stack-able, so the 2x10 need is
> easily met...
>
> They are available both with 11 pins, and more commonly with 4/5 pins
> giving BCD output--which would work with your suggested parts.

> On Tuesday 31 August 2004 05:28 am, ballendo wrote:
>
> > Another option is the 0-9 thumbwheel switches. I see these in ALL the
> > surplus places these days, and they ARE a rotary switch, just a 90
> > degree orientation change. Most are stack-able, so the 2x10 need is
> > easily met...
> >
> > They are available both with 11 pins, and more commonly with 4/5 pins
> > giving BCD output--which would work with your suggested parts.
>
> I have some of these, and have yet to come up with something I want

> them in...

> > Electro-mechanical encoders are quite cheap, they are made by ALPS and
> > Bourne. One of those with a small MCU and a display will do what you
> > want.
> >
> > Leon
>
> Thanks, but they are pretty useless for me.
> I can't change what i need, the IC expects a 2*10 switch.
> It is a charger, and meant to be "jumpered" for cell count, but i want
> a universal charger.

> --- In Homebrew_PCBs@yahoogroups.com, "Roy J. Tellason"
>
> <rtellason@b...> wrote:
> > On Tuesday 31 August 2004 05:28 am, ballendo wrote:
> > > Another option is the 0-9 thumbwheel switches. I see these in ALL the
> > > surplus places these days, and they ARE a rotary switch, just a 90
> > > degree orientation change. Most are stack-able, so the 2x10 need is
> > > easily met...
> > >
> > > They are available both with 11 pins, and more commonly with 4/5 pins
> > > giving BCD output--which would work with your suggested parts.
> >
> > I have some of these, and have yet to come up with something I want
> > to use them in...
>
> Handy for setting a device ID. Good when you have several devices on a
> bus, or wireless, that you want to identify.

>I need 2*10 positions, and can only get 2*6 or 1*12.
>For selecting cell count on a battery charger (no current at all).

> What IC is this? Do you have a link for a data sheet?
>

> At 04:27 PM 8/30/2004, Stefan Trethan wrote:
>
>> I need 2*10 positions, and can only get 2*6 or 1*12.
>> For selecting cell count on a battery charger (no current at all).
>
> <http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=26211&item=3836083832&rd=1>
> <http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=26211&item=3836173808&rd=1>
>
> There are others as well . . .
> <http://search.ebay.com/rotary-switch_W0QQcatrefZC6QQfromZR7QQnojsprZyQQpfidZ0QQsacategoryZQ2d1QQsacqtyopZgeQQsacurrencyZ0QQsaslopZ1QQsatitleZrotaryQ20switchQ2aQQsocolumnlayoutZ3QQsofocusZbsQQsopostalZT5SQ201K8QQsorecordsperpageZ50QQsosortorderZ1QQsosortpropertyZ1QQsspagenameZhQ3ahQ3afitemQ3aUS>
>
> dwayne
>

>Maybe do like was already stated earlier and just use LEDs around the
>dial to indicate position. Then don't put any position indicators on
>the dial itself. Then when you turn the unit on, you could have it
>start in the "home" position no matter how much the dial itself has
>moved while off.

> >
> > It seems i can't get rotrary switches with enough
> > positions.
> > Would be nice to be able to just make them how i
> > want.
> > After all it works in meters...
> And other place, a rotary switch is generally not cost
> effective, but it is the most intuitive, at least for
> those of us in the older generation. The youngsters
> may have grown up with bottom remotes etc, but I still
> have a few tv sets with rotary volume and channel
> select. EVen Fluke tried to go away from the rotary
> switch in the late 80's.... the product failed. They
> tried again with a lower priced model in the late
> nineties. I don't think its doing to well sales wise.

> I need 2*10 positions, and can only get 2*6 or 1*12.

> >
> >
> <http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=26211&item=3836083832&rd=1>
> >
> <http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=26211&item=3836173808&rd=1>
>
>Thanks, but ebay was the first i looked.
>I assume you either don't know i'm not in the US or you don't know what
>i'd have to pay for shipping and taxes...

> I had assumed that you were not from North America from your email
> address. That's why I included links only to sellers who ship
> worldwide. In particular, the 2nd link above is selling from Lithuania.
>
> dwayne
>

> i see.. thanks.
>
> ST

>> i see.. thanks.
>>
>> ST
>
>
> A big lesson: there is no such thing as "I already checked eBay." It's
> like watching a road for a certain car to go by, you can't look once
> and then say you've already checked.
>

----- Original Message -----
From: "Stefan Trethan" <stefan_trethan@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Wednesday, September 08, 2004 10:32 AM
Subject: [Homebrew_PCBs] Removing copper at one side


> Hi,
>
> I tried to peel off the copper at one side of a glassfiber pcb.
> I used a knife to separate the first layer of glass (with the copper)
> from the rest, at the edge, and then peeled.

I've removed small areas of copper by heating it with a large bit on my
soldering iron, after scoring it with a Stanley knife. It peeled off very
easily.

Leon

> I've removed small areas of copper by heating it with a large bit on my
> soldering iron, after scoring it with a Stanley knife. It peeled off very
> easily.
>
> Leon

----- Original Message -----
From: "Stefan Trethan" <stefan_trethan@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Wednesday, September 08, 2004 4:17 PM
Subject: Re: [Homebrew_PCBs] Removing copper at one side


>
> > I've removed small areas of copper by heating it with a large bit on my
> > soldering iron, after scoring it with a Stanley knife. It peeled off
very
> > easily.
> >
> > Leon
>
> That could just be a little bit too tedious for big areas.
> I tried heating with the heat gun and wasn't really convinced by the
> results...
>
> I guess i will etch the boards, further mechanical attempts were not
> leading
> to good results.
> I'll see if sticky tape is tight enough where it overlaps or if i need to
> use paint...

I've used both paint and masking tape. The latter allows some leakage, so a
waterproof tape
would be better. I've also used double-sided material with the unexposed
side as a ground plane. That
works very well.

Leon

>
> > I've removed small areas of copper by heating it with a large bit

> > soldering iron, after scoring it with a Stanley knife. It peeled

> > easily.
> >
> > Leon
>
> That could just be a little bit too tedious for big areas.
> I tried heating with the heat gun and wasn't really convinced by

> results...
>
> I guess i will etch the boards, further mechanical attempts were

> leading
> to good results.
> I'll see if sticky tape is tight enough where it overlaps or if i

> use paint...
>
> ST