SOLVED Paragon: No LEDs, Bypass works

[davebandit]

I didn't make any mods, just tried to build this one straight. I did bend the leads on the pots to cleat the bezels for the LEDs, but I don't see potential for shorting. All the pots have covers on them.

With 9v plugged in, I get nothing. I can trace the 9v power source to the anode on both LEDs

Pulled out of the enclosure for benchtop troubleshooting, this is the first build out of 4 that didn't fire up right out of the gate, so I'm not sure what's up.

Really appreciate the help.

 

[davebandit]

Probably worth mentioning I get no sound when either switch is activated, even after turning up the pots

I also tested the switches for continuity across the pins, and both switches seem to be operating ok.

 

[Barry]

Picture of the other side of the board?

 

[GenoBluzGtr]

while we wait on the pic of the underside here are a few items I would check:
- LED orientation. Long lead (anode) into the A-Hole. In some circuits, this keeps 9V from reaching the circuit... in others it simply keeps the LED from lighting, but circuit works.
- Wiring - especially where the wires go into the Footswitch breakout Board. If you use stranded wire, if one is not perfectly tinned - a stray single strand could bridge to the adjacent connector or wire. Those are REALLY close together.
- Check with a DMM for the correct DC voltage at the pins on the opamps... Pin 7, I believe?

Again, the LED's not lighting is an indication you're not getting 9V to or past the LEDs. start looking at power first.

 

[davebandit]

Sorry for the delay, here's the underside:

 

[davebandit]

LED orientation seems good, I even ran external 9v power to the LEDs separately and they lit up. Flat side on the LED is anode right? Both are facing "in".

Jumpers to breakout board look good, I tried tracing the board to I could check continuity, but that was pretty tough. Any idea of the best way to test the strands, I dont see anything obvious on visual inspection.

IC1: Pins 1-3 are around 8.9v, Pin4 Nothing, Pin 5-7 average 8.8v, Pin 8 17.74v
IC2: Pins 1-2 are around 8.9v, Pin3 8.11v, Pin4 Nothing, Pin 5-7 average 8.9v, Pin 8 17.74v

 

[Robert]

Flat side of the LED is the Cathode, so they might be installed backwards.

Incorrect LED orientation should not affect the rest of the circuit, however.

 

[davebandit]

Flipped LEDs, and now the LED on the "In" side of the board lights up!

The other side still does not light up. At least I am one step closer...

 

[Barry]

Time to start double checking component values

 

[davebandit]

Awesome, I did some re-flowing anywhere it looked like it could use it. And that appears to have fixed the audio issues (phew!)

At this point the last thing I am chasing is the LED on the OUT side of the board.

 

[davebandit]

Got it, I had to reflow each side of the breakout board led ground lead and add a slight amount of solder on the pad to make sure there was a connection. I had to desolder some standoffs which might have damaged the pad somehow.

Thanks, Everyone!