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Well hot dog! Thanks for your advice folks, the schematic was an unholy mess. Got that straightened out and it works! The tip about the voltages proved to be spot on (and probably a standard answer, lol).
Cheers...
pg

Will do - thanks very much. Like I said - a learning opportunity.

Thanks, I will check the pull down (of course I have to find out what that is exactly ).
Insofar as the IC voltages, I know one pin is at 9v and another at 4.5 ish), but I don't know what the others should be.
Clearly a learning opportunity.
regards,
pg

photos! I had a little soldering mishap, in the middle there, but there's continuity...

Greetings oh esteemed Etchers...
Been out of the loop for a while - decided to give this one a whirl:
https://www.freestompboxes.org/viewtopic.php?t=5592&sid=9d4ea6a30be719cd423cbd0cc9632ebb

Got a prototype soldered up and it's doing this weird thing, where it's reacting to the input volume. For example, I turn the guitar pot up to 10, the sound cuts out, but at 8 it works. It also fades in and out...

Something tells me it's a cap issue, but I simply don't understand what the issue could be nor where to start. While waiting for suggestions, I'll review the schematic for mistakes.

Any thoughts? Dazed and confused,
phil

Thanks for the help folks. In the end, the B50K pot was bad. Replaced that and we're good to go!
woohoo!

OK - that's good advice too. The resistors check out. I'll look at the ground on that pot too.
thank you!

good point. I'll get back to you

Well not exactly. When the feedback knob is fully counter clockwise, I get like 10-15 repeats. If I turn it up, it self oscillates at about 1/3rd of the way up...

Howdy folks,
Got back to the urchin, it works! It works too much! With the feedback pot turned all the way counter clockwise, now I get lot's of repeats, too many!
Any help is appreciated..
thanks

Ugh, never mind. Tried different tl072, pr2399, reflow. I have no idea, starting over.
peace,
pg

Or the lm78l05?

Folks,
I've learned my lesson on measuring voltages. I've got a Dimension P I've etched from a mask from Effects Layouts. It worked at bench test. After a test install in the 125B it stopped working. Grrrr.
So having learned my lesson I checked the voltages. There's two pt2399 and a tl072, voltage controlled with an lm78l05 trans. The voltages checked out at just about 5V. No explanation why the chorus effect wasn't working. Took it all apart, reflowed a few solders, rechecked the voltages - wow - 2V at pin 1. I sat back, thought about it for a minute, then checked again - 3V. What? Then about 2 minutes later, 5V. Now I'm scratching my head - AND I still don't have a chorus effect.

Seems to me I have a wonky capacitor somewhere. But wth do I know...

So - is my guess correct, or is there something else I should check.?
thanks,
pg

Thanks, learn something new every day! Much appreciated.
phil

Howdy Folks,
Built a ts808 from a schematic. The overdrive is an A500K pot, it works, but the overdrive decreases as the pot is turned clockwise. In the snip of the schematic it looks like pin 1 is open. I've tried a reverse pot and switching the wires but nothing doing... Suggestions anyone?
much thanks
phil