808 Handclap (almost there)

jbeuckm · Posted: Thu Aug 27, 2015 5:46 pm Post subject: 808 Handclap (almost there)

The simple noise envelope is working but the clackity clack is not happening. Help me debug!

I substituted the BA6110 but did not build the current mirror as suggested here: http://www.firstpr.com.au/rwi/dfish/TT-303/click-fix/

Could that be the problem?

Eagle files are here:

https://github.com/jbeuckm/808-Handclap

bad_808_clap.mp3

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Screen Shot 2015-08-27 at 7.43.03 PM.png

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LFLab · Posted: Fri Sep 04, 2015 4:23 am Post subject:

Started to have a look at this one in Eagle, I used your schematic, but started to reroute to have all resistors lying down, a bit more compact, and adjustments for parts which I have in my bin.

I'll try to spot mistakes before committing this to an iTEAD order Very Happy

Did you see these?
Yocto build tips
E-licktronic (Yocto) errata

jbeuckm · Posted: Fri Sep 04, 2015 7:14 am Post subject:

Thanks! I'm pretty excited to get home and flip C144... There are plenty of things to measure and try here.

jbeuckm · Posted: Tue Apr 26, 2016 9:03 am Post subject:

@LFLab Any luck? I have restarted this layout from the Yocto eagle file. I probably had a bad connection or wrong value on my first version. Also, I am moving to 2N390x transistors this time to avoid any pinout variations. I'm doing the reverb mod too.

LFLab · Posted: Tue Apr 26, 2016 9:17 am Post subject:

I actually did a layout....for the 909 clap Very Happy

Nothing going on on my end on the 808 clap.

jbeuckm · Posted: Tue Apr 26, 2016 9:36 am Post subject:

Very similar circuit. Which OTA did you use?

LFLab · Posted: Tue Apr 26, 2016 11:36 am Post subject:

CA3080, usually I'd replace this with 13700, but for the life of me I couldn't figure out what to do with the other section, and I do have quite a few of them around.
It only exists in Eagle now though Smile

I used hexinverters neinohnein schematic, so that should be good.

I have some grief with the Yusynth Quadrature LFO to deal first Crying or Very sad

jbeuckm · Posted: Tue Apr 26, 2016 2:45 pm Post subject:

Oh that's easy - use the other half of your 13700 to CV the reverb level Wink

jbeuckm · Posted: Wed Apr 27, 2016 8:55 pm Post subject:

Woohoo - verified! I had to change C140 to 27n to get separated hits (2n7 in the service manual). This has reverb level on a 16mm edge pot. Requires separate noise source.

https://github.com/jbeuckm/808-Handclap/releases/tag/v0.1

808_clap.mp3

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LFLab · Posted: Thu Apr 28, 2016 3:28 am Post subject:

Very nice! cheers

ADMST · Joined: Oct 27, 2016 Posts: 2 Location: NYC

Man, your work is inspiring! Will this design run at +/- 15v ??

jbeuckm · Posted: Tue Dec 13, 2016 8:08 am Post subject:

Yes. The original was 15v afaik. I think I actually used a +-15V power supply on mine through a euro connector.

ADMST · Joined: Oct 27, 2016 Posts: 2 Location: NYC

Amazing. Thank you!

artilect99 · Joined: Oct 01, 2018 Posts: 51 Location: USA

Sorry for the noob question, but I've never had a PCB fabbed before. How exactly does one go about getting a PCB made from files such as these? Do I need eagle in order to convert them to gerber files?

lilpaula87 · Joined: May 11, 2020 Posts: 12 Location: Italy

Wow I’m really interested in this project but I already have a midi to cv and a cv to trigger module. There’s a way to slightly modify this pcb to add an external input for trigger and accent?