SOLVED Octarock Not Turning On

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Pufftones

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Hey, so my title pretty much says it. This is my second build. When turned off, signal passes through the pedal and I get a clean sound. When turned on, the light on the footswitch does not turn on and everything goes silent. Here are some photos. Let me know if you see anything suspicious or if more photos would be helpful. 20230512_183749.jpg 20230512_183738.jpg 20230512_183729.jpg 20230512_182342.jpg 20230512_182339.jpg 20230512_182311.jpg
 
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NickC said:
I just finished my octrarock everything works perfectly except the low octave, strangely I tried to remove and replace the second jrc and for a few seconds and then faded I heard the lower octave as it should sound, so if you got these components like me on banzai music the problem could be this.

update: I'll tell you more, I noticed that if I touch pins 3 and 4 with a screwdriver the low octave returns and then slowly discharges until it vanishes again.

another thing, if i switch from 9 to 12 V, for few second the octave down works and than if fades away, so i think its the jrc.
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I've been meaning to update this for a while. I ended up just starting over and the second one worked like a charm straight out of the gate. I had...
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You need to jumper the LED pads on the main board.
Otherwise, everything looks good at first glance. Would it be possible to see the other side of the board?
 
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Just need to run a piece of wire to connect these two holes. Since you're using the 3PDT mounted LED, leaving those open leaves the LED circuit open
Screenshot_20230512-173222.png


I'll examine your photos more closely when I get back home
 
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DGWVI said:
Just need to run a piece of wire to connect these two holes. Since you're using the 3PDT mounted LED, leaving those open leaves the LED circuit open
View attachment 48451


I'll examine your photos more closely when I get back home
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I ran the jumper this morning. That certainly moved things forward a bit. Now the LED on the footswitch turns on and I get some static when it's turned on. Still not functioning though.
 
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Pufftones said:
I ran the jumper this morning. That certainly moved things forward a bit. Now the LED on the footswitch turns on and I get some static when it's turned on. Still not functioning though.
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That was just to fix the LED issue, it won't have any bearing on the rest of the circuit.

Honestly, I'd start by suggesting you clip the leads on all the components a bit shorter, there are a couple spots that look like they could be bridging. Then, I'd touch up any joints that look suspect- particularly those for the in/ out/ gnd/ SW

Which JFETs did you use?
If using 2N5457 from Tayda, they may be bunk. They caused issues in my first two Octarock builds as well

Are you able to measure voltages?
 
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After you trim the leads, go around and “reflow” the solder everywhere. I just do this as part of my process, but I’m coming to realized that I am a belt, suspenders, and whatever else it takes kinda guy. In any case, most of the time when I don’t fire up right away, it’s a joint like the one I’ve circled—note how the solder doesnt flow onto the entire pad—since that’s the side you were soldering from, that might indicate a cold joint.

EC4F5426-DF1A-4991-BBB5-51F1AAB12F8E.jpeg
 
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Betty Wont said:
I’ve successfully built these with a variety of fets. Through hole, smd, 5457 and j201. I think they are just buffers. No strict requirements.
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Ok, that was one of my other quesitons. The components list said to use an MPSA18 but the boards says MPSA13. I didn't catch this until I had already ordered the 18's so I just rolled with throwing one of them on there but wasn't sure if this would cause an issue.

I'm about to give a couple of the suggesting here a try. If it works, I'll update. Otherwise, I may go quiet for a bit because I'm going to a show with my partner tonight and then have to travel for work for a few days.
 
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Pufftones said:
Ok, that was one of my other quesitons. The components list said to use an MPSA18 but the boards says MPSA13. I didn't catch this until I had already ordered the 18's so I just rolled with throwing one of them on there but wasn't sure if this would cause an issue.

I'm about to give a couple of the suggesting here a try. If it works, I'll update. Otherwise, I may go quiet for a bit because I'm going to a show with my partner tonight and then have to travel for work for a few days.
Click to expand...
Mpsa13 or 18 works fine.
 
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Betty Wont said:
I’ve successfully built these with a variety of fets. Through hole, smd, 5457 and j201. I think they are just buffers. No strict requirements.
Click to expand...

The first two Octarocks and an OC-07 clone I built at the same time would not function properly with the batch of Tayda sourced 5457s I had. They worked fine for the input buffer, but the buffer after the 4013 signal is biased differently, and that seems to make it more sensitive to the JFet used.
Though, that shouldn't make the whole circuit not work. My issue was limited strictly to the lower octave
 
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DGWVI said:
The first two Octarocks and an OC-07 clone I built at the same time would not function properly with the batch of Tayda sourced 5457s I had. They worked fine for the input buffer, but the buffer after the 4013 signal is biased differently, and that seems to make it more sensitive to the JFet used.
Though, that shouldn't make the whole circuit not work. My issue was limited strictly to the lower octave
Click to expand...
I didn’t know that Tayda has had 5457 for sale for years.
 
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Ok, I'm still just getting static when I turn it on BUT the knobs do change the frequency and level of the static which would indicate that some signal is making its way through the pedal. I might end to replacing the small board on the switch because I've spent way too much time trying to get the old solder out of the hole for the ground and can't. I've got a wire stuck there but getting one through has been completely impossible. This might be part of the problem but I'm also going to try to replace those JFETs.

Also, I was mistaken. The MPSA 18 was from Tayda. The 5457's were from GuitarPCB.
 
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