Finished this but am getting nothing but slight ticking with rate pot. I double checked for errors but it looks bang on with the layout. I have a feeling it might be my trs jacks. I'll try alternate wirings later.
Luckily, I found a little error in the layout: is missing one cut at K14 (between base of Q1 an pin 5 of IC2). After I added, it works OK. I used BC550C instead of 2N5089 (must be flipped) and I wired the frequency and rate pots directly to the board (I have no expression pedal).
I just finished boxing it and can confirm it's 100% working properly. Regarding your "a" half not working... Not sure if you checked that your "mix a" pot is turned high enough. With it turned all the way ccw, you won't hear the "a" side. Also make sure your "frequency" pot is turned at least half way up.
Thank you very much, Mike! I will recheck all. It's clear that I made a mistake. With all pots from A side maximized and all pots from B side minimized, I can hear only clean signal.
I've built this two times with the exact same result... can't get it to work. All I'm getting is some high pitch whine when engaging the mixes and a somewhat amplified sound. Do the transistors have to be matched or something? Turning the potentiometer does have an audible effect but nothing like the pedal is supposed to sound. Any ideas?
Hey there - I've built this a couple times successfully and there was no matching of semiconductors required. There will be a little whine accompanying the oscillation but it is not the primary sound. One thing I would suggest to simplify things a little was what I did the first time - that was to build it without the expression jacks and wire the pots that they control directly to the board. It will eliminate one of the potential areas for error. Good luck!
Hi Chris, thanks for the info. It's the same when I bypass the expression jacks (I had tried that when I was troubleshooting my first build). I'm beginning to suspect some bad quality transistors or something. I'll try some alternatives.
Is the 1uf cap on the right a polarized electro, or a poly?
ReplyDeleteIt is a non polarized electro or poly.
DeleteFinished this but am getting nothing but slight ticking with rate pot. I double checked for errors but it looks bang on with the layout. I have a feeling it might be my trs jacks. I'll try alternate wirings later.
ReplyDeleteBtw these are the jacks I'm using.
ReplyDeletehttps://www.taydaelectronics.com/6-35mm-1-4-stereo-insulated-switched-socket-jack-solder-lugs.html
Luckily, I found a little error in the layout: is missing one cut at K14 (between base of Q1 an pin 5 of IC2). After I added, it works OK. I used BC550C instead of 2N5089 (must be flipped) and I wired the frequency and rate pots directly to the board (I have no expression pedal).
ReplyDeleteThank you very much, fuzzhead! You're fantastic!
You are fantastic as well, Radu.:-)
DeleteThanks for verifying and spotting the missing cut.
Tagged.
Thank you, fuzzhead...but you are too modest :)
DeleteThat's all it was. After the cut at k14, everything works well. What a crazy circuit!
ReplyDeleteGlad to help you, Mike! I hope that today I will have more time to play with it. Anyway, two separated LFOs could have more fun :)))
DeleteGreat catch. I put the circuit away and kind of forgot about it. Thought it was probably the trs jacks, turns out it was just a simple cut.
DeleteToday I have more time to play with it and I saw that only its B half works OK. Have you tested yours completely? All pots works OK?
DeleteI just finished boxing it and can confirm it's 100% working properly. Regarding your "a" half not working... Not sure if you checked that your "mix a" pot is turned high enough. With it turned all the way ccw, you won't hear the "a" side.
DeleteAlso make sure your "frequency" pot is turned at least half way up.
Thank you very much, Mike! I will recheck all. It's clear that I made a mistake. With all pots from A side maximized and all pots from B side minimized, I can hear only clean signal.
DeleteI found an unsoldered pin of an IC :)
DeleteNow sounds OK...very interesting effect!
How would one delete the trs jacks?
ReplyDeleteIs it as simple as removing them or are jumper wires required?
I'm sure I wired the trs jacks incorrectly.
Found my answer on page 5 of pedal PCB build doc.
ReplyDeleteI've built this two times with the exact same result... can't get it to work. All I'm getting is some high pitch whine when engaging the mixes and a somewhat amplified sound. Do the transistors have to be matched or something? Turning the potentiometer does have an audible effect but nothing like the pedal is supposed to sound. Any ideas?
ReplyDeleteHey there - I've built this a couple times successfully and there was no matching of semiconductors required. There will be a little whine accompanying the oscillation but it is not the primary sound. One thing I would suggest to simplify things a little was what I did the first time - that was to build it without the expression jacks and wire the pots that they control directly to the board. It will eliminate one of the potential areas for error. Good luck!
DeleteHi Chris, thanks for the info. It's the same when I bypass the expression jacks (I had tried that when I was troubleshooting my first build). I'm beginning to suspect some bad quality transistors or something. I'll try some alternatives.
Delete