Paragon *no sound from CH1

Lewage

New member
Just finished populating this board this afternoon. Hooked it up and CH2 sounds great. Switched to CH1 and I get almost no sound. *If I mess with the pots enough I can get the occasional quick fart out of it.
Anyone notice something stupid here?
 

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Can you take some additional pictures? These are very difficult to see resistor bands and solder joints. :)
 

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R4 looks like 39kΩ instead of 33kΩ but that's a non-issue. Are you getting signal to the pcb (@ CH1 switch)?
Yes. I ran an audio probe across it and it works at every joint. That said, it was my first time using one, so I may not have been doing something correctly.
I knew about the 39ohm resistor. I was out of 33s and figured that shouldn’t really have an effect.
I even swapped the ICs since I knew channel 2 was working.
 
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Try the audio probe at pins 1 & 7 of IC2. That will tell you if signal is passing through the 2 stages of the 1st channel op amp.
 
So I lied about pin 1 I'm getting a signal, but it fizzles out if I leave the probe on there. Also noticed that I get no sound from pin 2 unless I "accidentally" bridge 1 & 2. Then both pins do the fizzling out thing when I probe them seperatly.
 
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I set the dip switch and pots of both channels the same so that I could switch back and forth to compare. That's when I realized how bad pin 1 on IC2 was sounding.
 
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I'm thinking it should be around -4.50v, but...what about pin 3 of IC1?
Right around 7.50
I have another board. I think I'm going to try and salvage a couple diodes and move on.
I'll keep this one around in case I get really bored.
I REALLY appreciate you troubleshooting this with me!
 
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