Earthquaker Devices Zap Machine V2

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graybench
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Post by graybench »

I've been hunting down this pedal for a while after EQD featured it on their youtube channel.
This is second version, 350 made for prymaxe. There is a V1 of which only ~20 were made.


zapmachinev2.jpg
PCBtoptraces.jpg
PCBbottraces.jpg

Here is my guess for V1 based on the screenshot below from that youtube video. THIS IS AN APPROXIMATION, USE WITH CAUTION.
Specifically, I'm not sure about the emitter connection for Q2, either the 1K or 470R might be an emitter resistor.

zapmachinev1guess.jpg
Untitled.png
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Nocentelli
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Post by Nocentelli »

modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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graybench
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Post by graybench »

Pretty much. Different tone control, no buffer, germanium Q3, otherwise you're basically there.
Could also mod a scarab deluxe in a V1 by pulling Q4 and connecting a 1u cap from the base through-hole of Q4 straight to the volume pot. Maybe swap Q3 for a low gain germ if so inclined.

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Post by Nocentelli »

graybench wrote: 30 Mar 2023, 03:35 Different tone control.....
Yeah, that's the SWTC isn't it? Don't see it in many commercial pedals (the pre-Q1 bass cap blend is also not too common, as soon as I saw it I thought of the scarab)
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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Post by graybench »

Nocentelli wrote: 30 Mar 2023, 07:55
graybench wrote: 30 Mar 2023, 03:35 Different tone control.....
Yeah, that's the SWTC isn't it? Don't see it in many commercial pedals (the pre-Q1 bass cap blend is also not too common, as soon as I saw it I thought of the scarab)
Yep, last one on this page: http://www.muzique.com/lab/swtc.htm. Should have given a shoutout in my video but I didn't realize it at the time.

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Post by Ben N »

Nice work as always. Any chance of a Gerber?

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Post by graybench »

Ben N wrote: 23 Apr 2023, 20:33 Nice work as always. Any chance of a Gerber?
Sure thing, attached.
Also Bugg has a PCB coming out: https://www.pedalpcb.com/product/pcb580/
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Post by Ben N »

graybench wrote: 24 Apr 2023, 12:48
Ben N wrote: 23 Apr 2023, 20:33 Nice work as always. Any chance of a Gerber?
Sure thing, attached.
Also Bugg has a PCB coming out: https://www.pedalpcb.com/product/pcb580/
Thanks! That's great news about Bugg (I've built on a lot of his pcbs), but I think I like your single channel version better--it does everything the original does, but without extra size & complexity.

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Post by graybench »

Ben N wrote: 24 Apr 2023, 13:55
graybench wrote: 24 Apr 2023, 12:48
Ben N wrote: 23 Apr 2023, 20:33 Nice work as always. Any chance of a Gerber?
Sure thing, attached.
Also Bugg has a PCB coming out: https://www.pedalpcb.com/product/pcb580/
Thanks! That's great news about Bugg (I've built on a lot of his pcbs), but I think I like your single channel version better--it does everything the original does, but without extra size & complexity.
I've had a bunch of people asking for more, so I think I am going to do one more order for PCBs. I'm not trying to be a PCB seller though, but I get what you're saying about the single channel thing.

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