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Subject: Re: [ModularSynthPanels] Re: SOST Flanger panel discussion

From: Scott Juskiw <scott@...>
Date: 2009-10-03

Yes, the LFO MODE switch matches what JH has in the schematics (and
his prototype). Looks like you have everything accounted for. Thanks
for doing this. When I get the PCBs I will build it to this layout and
let you know if the BPOL switch is worth having or not. Also, I have
some different ideas about how to implement the V/OCT tweak pot. I
might need to add a MUUB board for a buffer or two.

On 2-Oct-09, at 11:33 PM, wjhall11 wrote:

> How's this look
>
> http://www.dragonflyalley.com/images/JHSOSTFlanger/JHSOSTFlangerV4vIIwidth2-56in.jpg
>
> Did I place the LFO Modes correctly? I was just guessing.
>
>
> --- In ModularSynthPanels@yahoogroups.com, "wjhall11" <wjhall@...>
> wrote:
>>
>> Ok - I see how we could easily use one dpdt for the bypass switch.
>> We were interpreting Jurgen's "schematic 6" literally. The DPDT
>> idea looks better. If the switch hole is centered 1/2in from the
>> edge, it would still be possible for people to use a 4 pole switch
>> if they wanted to.
>>
>> There really isn't room for two rows of switches - at least not to
>> my eye... but I just did a trial and I think we could get all the
>> switches in. I'll post it later.
>>
>>
>>
>>
>>
>> --- In ModularSynthPanels@yahoogroups.com, Scott Juskiw <scott@>
>> wrote:
>>>
>>> I wasn't planning on using a 4PDT switch for bypass. My plan is to
>>> use
>>> a regular 2PDT switch connected to just the outputs: in the active
>>> position the outputs are connected to the flanger outputs, in the
>>> bypass position the outputs are connected to the inputs. This means
>>> the inputs are always connected to the flanger, even in bypass mode,
>>> but I see no significant disadvantage in doing so, and a significant
>>> advantage in that I can use a regular switch. But if you really want
>>> the inputs to switch as well, then I agree with you that two 2PDT
>>> switches is probably a better choice than a 4PDT.
>>>
>>> Panel mount trimmer? Hmm, I'm not so keen on having to dig out a
>>> little screwdriver every time I need to tweak the 1V/OCT setting.
>>> I'd
>>> probably wind up scratching the panel with the screwdriver tip. I
>>> say
>>> make it a pot (maybe a small knob), or leave it out entirely. Maybe
>>> it's not even worth adding. I'll have to try it out when I get the
>>> PCB.
>>>
>>> Can you put the switches into two rows?
>>>
>>> On 2-Oct-09, at 12:43 PM, wjhall11 wrote:
>>>
>>>> The hard constraint so far as the row of switches is concerned is
>>>> only that the BYPASS switch is 1/2in from the edge of the panel
>>>> because it's a 4PDT switch and needs the space.
>>>>
>>>> BTW, let's all remember that it only comes as a regular "bat"
>>>> toggle
>>>> rather than the flattened ones that are MOTM standard. Will was
>>>> considering disassembling a MOTM standard SPDP switch to see if we
>>>> could transplant the toggle (assuming matching blood-types).
>>>>
>>>> At any rate - the point is that wherever that bypass switch is
>>>> placed (it makes sense to be either the left or right extreme), it
>>>> needs about 1/2 in on either side of its center. Other than that
>>>> there's plenty of room for another switch like the On-Off-On
>>>> (M201302) switch Scott's mentioning.
>>>>
>>>> OK - well - there's another possibility re the bypass switch - use
>>>> two DPDT 201202 switches - one for left, one for right. I'm
>>>> starting to like that idea better.
>>>>
>>>> But anyway - Scott - could the 1V/oct tweak function be handled
>>>> by a
>>>> panel-mount trim pot a-la the Living VCO? (Trimmer (assumes 100K):
>>>> Mouser# 594-43P104 and Panel-mount: Mouser# 594-611) That would
>>>> save space on the panel, too.
>>>>
>>>> If BYPASS is implemented with two switches, LFO MODE with an on-
>>>> off-
>>>> on, and a BPOL switch added, I think we could still fit it all
>>>> nicely if we use a panel mount trimmer for 1V/oct rather than a
>>>> pot-
>>>> and-knob.
>>>>
>>>> Just thinking.
>>>>
>>>> Bill
>>>>
>>>>
>>>>
>>>>
>>>> --- In ModularSynthPanels@yahoogroups.com, Scott Juskiw <scott@>
>>>> wrote:
>>>>>
>>>>> I don't have the PCBs yet but I'm already working out some of the
>>>>> details for this module. Bill and Will already have a panel
>>>>> proposed
>>>>> for this (search for "flanger" on this page):
>>>>>
>>>>> http://www.dragonflyalley.com/billAndWillMOTMSynth.htm
>>>>>
>>>>> which I like, but there are some options to consider.
>>>>>
>>>>> 1. You don't need a rotary switch for LFO MODE. You can use one of
>>>>> those 3 position centre-off switches. This frees up pot space
>>>>> for a
>>>>> 1V/
>>>>> Oct tweak pot (this is shown as an option in the schematics). JH
>>>>> has
>>>>> mentioned (on an electro-music forum) that the 1V/Oct tracking
>>>>> is not
>>>>> so good, so having a front panel pot may be a good idea.
>>>>> 2. Can add a jack for LFO OUT (will likely need to add a buffer as
>>>>> well). This would be post-LFO MODE switch, so the output will be
>>>>> either ramp, slewed square, or S&H depending on LFO MODE setting.
>>>>> 3. There is a BPOL (bounce polarity) switch on the schematic.
>>>>> Hmmm,
>>>>> first one who builds one of these will have to let us know if it's
>>>>> worth implementing or not.
>>>>>
>>>>> I'm still trying to figure out how best to hook up the LED.
>>>>> Should it
>>>>> indicate the LFO (i.e. post-LFO MODE switch) or the total delay
>>>>> time?
>>>>> This doesn't change the panel layout. I'll need to try out
>>>>> different
>>>>> things after I get the boards in.
>>>>>
>>>>
>>>>
>>>>
>>>>
>>>> ------------------------------------
>>>>
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>>>>
>>>>
>>>>
>>>
>>
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