Building the tap tempo tremolo

[Taylor]

Those subs should be fine. The 1u caps are in the signal path too. Try building an audio probe and probing from the input to the output. The signal path is quite short so it should be simple to isolate.

If you're using a proper 9v regulated supply, you seem to have a problem with your 9v rail (pin 8 of the opamp).

Also, I recommend setting all trims and external pots to a middle setting while trying to get t to work.

[sdb guitars]

Thanks, Taylor.

When I did the voltage testing, I was using a battery, though when "amp testing" I used a OneSpot, same results.

I'll build a probe and test it out...

Out of curiosity, I noted several small tinned holes on the board with no instructions on what to do with them (no parts to place, no jumpers listed, etc.). Are those test points of some sort?

Thanks again,

Shawn.

[lwatford]

I've had an interesting issue come up. I recently bought a Timeline, and when I put the Tremolo on while the Timeline is on, I get a high pitched whine. I added filtering at the DC Jack, but didn't notice a difference. I've not had this issue with any other delays (including a El Capistan). I tried putting a buffered pedal between the two, no difference.

any ideas?

[Taylor]

Out of curiosity, I noted several small tinned holes on the board with no instructions on what to do with them (no parts to place, no jumpers listed, etc.). Are those test points of some sort?

They are vias. They connect traces on the top layer to traces or ground pours on the bottom layer. You can ignore them.

I've had an interesting issue come up. I recently bought a Timeline, and when I put the Tremolo on while the Timeline is on, I get a high pitched whine. I added filtering at the DC Jack, but didn't notice a difference. I've not had this issue with any other delays (including a El Capistan). I tried putting a buffered pedal between the two, no difference.

any ideas?

Hmm, it's possible that the PWM frequency of the trem is heterodyning with some clock in the Strymon. Might be something to ask Tom Wiltshire about (electricdruid.net)

[roseblood11]

I've had an interesting issue come up. I recently bought a Timeline, and when I put the Tremolo on while the Timeline is on, I get a high pitched whine. I added filtering at the DC Jack, but didn't notice a difference. I've not had this issue with any other delays (including a El Capistan). I tried putting a buffered pedal between the two, no difference.

any ideas?

What happens if you power the tremolo with a battery?

[lwatford]

It does the same thing with a battery and/or separate power supply for the timeline. The half speed-ed squeel is around 10k, if that makes any difference.

[sdb guitars]

Managed to get the trem working, but getting an ungodly loud pop when turning it on, every time. Works normally when turning it off. Is there a pull down resistor built into the board?

[Taylor]

Yes. See the schematic for details:

http://musicpcb.com/documentation/

[acehobojoe]

When do you use the 2N3904? I can't see it on there, it was on the bill of materials.

[Taylor]

It's in the center of the board, below the trimpots. The flat side should face toward the trims.

[smacca]

so about 9 months after i mentioned it, i still can't access the site due to virus 

[Taylor]

Thanks for letting me know. There's no virus. Hackers keep hiding spam links in the site for SEO purposes. I fix it, they hack it again. People are still able to use the site regularly. If you're afraid of going on the site, you can always PM me regarding what you'd like to purchase and I'll let you know how to send a Paypal payment to me directly.

It's not that I don't care about this, it's that I don't know what to do to fix it permanently. Any suggestions are welcome.

[lwatford]

Sorry to keep asking questions...I think I've just got clock noise bleeding through. I tried it with a different delay (DL4) and it did similar things when I dropped the loop speed. I also noticed that if I listened very carefully I could hear the whine in the background at all times with it on.

[9aul]

Thanks for all the help from various people on this post. Got it working (after some stupid mistakes) and it sounds great.
Also had my first go at etching a design in the enclosure. I used 1:1:1 mix of Hydrochloric acid (32%), hydrogen peroxide (40%) and water. worked great on a test piece but then on the actual enclosure, because its much larger it heats up a hell of a lot so speeds up the reaction, so I really over cooked it. There are probably a few other things I did wrong so it ended up looking a little scrappy, but luckily I was kind of after a worn effect so don't mind it so much.


Anyway, pedal works great. Well worth the build

[Taylor]

The etch looks good! Also nice typeface for the controls, it goes well with the etch.

[acehobojoe]

Building my first one in a week or so. Don't know if this has been asked yet, but I was wondering a few things.
1. What enclosure would be ideal?
2. There is a way to bring in external clock pulses, is there a dial of some sort that I could use to dial in a specific number?
3. I noticed many were having problems with "clicks", so I guess the only solution is involved with the LED's resistor?
Thanks.

[Taylor]

The 1590BB is about the right size.

I don't understand your question about clock pulses - when you mention dialing in a number, what do you mean?

[acehobojoe]

would it be possible to have a number to type in for the tempo speed? like 120 bpm or something. Maybe there's a way to send a tempo control to that.

[Taylor]

That's not possible with the stock circuit/code. If you happened to have something like the Pamela's Workout module by ALM (this is a Eurorack synth module) then you could set the BPM on it and send 1ppqn clocks from it to the trem.

[acehobojoe]

ok, then it's just a matter of putting a "clock in" 1/4 inch. Thanks! I hope I can try that. Anything I should be careful about?