VCS3 Card for 208 and Easel build thread

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bishopmagicdonjuan
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Post by bishopmagicdonjuan » Thu Dec 05, 2019 12:08 am

is there a way to adapt this into a MU module???

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papz
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Post by papz » Thu Dec 05, 2019 6:04 am

Mounting the PCB into a MU module is possible as long as you can take care of the adaptation, panel and mounting yourself.
The edge connector pinout is in the build notes.
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I'm not a synths dealer and don't know of any cheap Synthi secret market.
I don't offer support for attempts to build clones of EMS equipment.
Please don't ask, thanks.

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Re: VCS3 Card for 208 and Easel build thread

Post by papz » Thu Jun 25, 2020 12:13 pm

It is possible to scale the frequency input banana for 1V/oct or 1.2V/oct by adding a 100k trimpot in parallel with the 75k resistor. I'll likely add this feature to the PCB for the next run.

I can get good tracking over 4-5 octaves with a single turn 3362 trimmer but you can use a multiturn 3296 one for more accuracy.

Solder 2 legs of the trimmer (the central one and another one or the other, it's the same) and leave the third leg unconnected (you can snip it) as shown on the pics.

Then turn the frequency attenuverter pot fully CW, switch the "key" switch to the low position, patch your CV source to the banana socket and adjust the added trimmer to get correct scaling, I tested with the 218e 1.2V/oct but should work perfect with 1V/oct.
So when you want scaled CV, you'll simply turn the pot fully CW, no further adjustment will be needed.

IMG_1370.resized.JPG
IMG_1371.resized.JPG
Finest EMS gear service and Music Easel/208 goodies

I'm not a synths dealer and don't know of any cheap Synthi secret market.
I don't offer support for attempts to build clones of EMS equipment.
Please don't ask, thanks.

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makers
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Re: VCS3 Card for 208 and Easel build thread

Post by makers » Wed Aug 05, 2020 4:16 pm

I don't want to sound ungrateful for a thorough BOM for this- but does anyone have a Mouser Cart with most of the parts sourced there. I've never actually orderd anything from Tayda. Being in the states, Mouser has been my primary source for convenience.

A little part of my soul dies when I think about the time it takes to source passives.

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papz
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Re: VCS3 Card for 208 and Easel build thread

Post by papz » Wed Aug 05, 2020 4:27 pm

I never heard about a Mouser cart but most parts are very common.
Tayda is a nice supplier way cheaper than Mouser for small quantities and offers various ww shipping options from registered mail to express delivery in a few days.
Finest EMS gear service and Music Easel/208 goodies

I'm not a synths dealer and don't know of any cheap Synthi secret market.
I don't offer support for attempts to build clones of EMS equipment.
Please don't ask, thanks.

User avatar
papz
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Re: VCS3 Card for 208 and Easel build thread

Post by papz » Sun Mar 14, 2021 1:41 pm

I updated the build notes with reference designator to help locate the parts in the original Synthi A / VCS3 oscillators 2 and 3 and noise schematics.
http://www.portabellabz.be/images/vcs3/ ... _notes.pdf
Finest EMS gear service and Music Easel/208 goodies

I'm not a synths dealer and don't know of any cheap Synthi secret market.
I don't offer support for attempts to build clones of EMS equipment.
Please don't ask, thanks.

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