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Not too long ago, I wondered if I could add a chorus/vibrato selector switch to the Touchstone (Small Clone). Mr. Bean said all I needed to do was lift R6 for vibrato mode, so I rebuilt my enclosure with a spot for a switch and it turned out great! Excellent warbel.

Removed R6 (22k) and ran wires from its pads to the center of the DPDT ON-ON that I positioned between the pots. The chorus side of the switch has the 22k resistor, the vibrato side is empty - breaking the clean tone side of the circuit.

I piggybacked a parallel 750k over the top of the 1M, bringing it down to 428k. I hear modulation now! Sounds cool.

Hello,

I dug out my Touchstone today and I've been thinking it would be cool to have a chorus/vibrato switch.

If I put a SPDT On-On-On in the circuit just after Q2 to either continue the original circuit or send the signal from that spot straight to output, would that work?

Thanks!

If you use the 1M resistor it is subtle. If you give the strings a good thwacking you'll hear the modulation, esp. with long delay times. Follow the suggestion in the doc if you want to increase the modulation response.

OH YEAH! That's right. Thanks for the reminder. Time to mod the mod. 

I'm wondering if I need check the continuity of that switch. I'm not noticing much of a difference either way. Is it subtle?

I had an excellent time with this. My first build with a soft-touch switch, and I think I'm in love.

I love that enclosure color. I gotta scoop some of those. Is it a tayda box?

Yep.

Man, you can't beat this for a free PCB. Sounds great! Adds to the headroom of a clean humbucker almost like it's running at 18v. Love it!

I'll be here. 

It's April 15th and I CAN'T WAIT TO BUY A SETBACK! The FX90 was the first delay pedal I ever owned and now I get to build one!

I have come back to end this thread and accept my badge of shame. Yes, I did have a matched set of JFETs. Unfortunately they were 2N5952s that I got from guitarpcb.com and I forgot to invert them on the board. Case closed. 

Hello,

I am working on the latest version of the NomNom (Phase 90). I am getting a clear signal when engaged but not phasing. I have been through the board with an audio probe and the clean signal/rate pot section seems to be the problem. I have signal at the emitter of Q1, but when I move on to R25, and the other spots in that section (including the right side of IC1), I get a faint heartbeat type flopping noise that speeds and slows when I adjust the pot. The left side of IC1 is passing signal as normal, along with all the other two ICs. I've tries adjusting T1 with no change. Voltages seem okay. I've tried 4 different TL072s in IC1 with no change. Hoping this is a common thing that someone will notice right away. Thanks!

1 Spot power supply at 9.42v

On all three ICs  1-3 and 5-7 are  3.85v, 4 is 0 and 8 is 9.16
Q1 is 2.27C 2.8B 3.85E
Q2-5 all three pins are at 3.85 or very close to it

Latest Update:

https://youtu.be/_roeEcxS7ek

I got the 8038 on eBay from here:

https://www.ebay.com/itm/2PCS-INTERSIL-ICL8038CCPD-ICL8038-Waveform-Generator-Oscill-Gen-DIP-14-IC-New/291565457594?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Looks like they're still in business with a 99.8% rating, although the top review says "Counterfeit IC's all 5 where bad. Replaced with another vendors product all work
5PCS National Semiconductor LF351N LF351 JFET Input Op-Amp and Machined"
Sooooooooo.....hmmm. I bought two of them and have tried both.

I got the AD633 from Mouser.

Sounds like maybe the 8038? Would be nice to have one from a legit source. Does anyone besides Small Bear sell them?

Thanks for the reply!

Ok, nothing? Here’s some more:

I reseated all the ICs. I changed out the shift and mod pots for new, as the first ones I used had been salvaged from a previous project. I started tracing with an audio probe and started getting an effect signal all the way to the end. I plug a guitar into it and I am getting effected signal, but the pots have no effect. The signal stays the same no matter which way I turn them.

Annoying.