SOLVED Angry Charles - little to no sound

[pdfermat]

So just finished the build, led comes on, but no sound (barely any - I can hear the tiniest bit of guitar signal through the amp). Bypass works fine.

Voltages on the ICs read:

IC 1 (LM833N)
Pin 1 4.70v
Pin2 4.70v
Pin 3 4.28v (and both clipping LEDs light up)
Pin 4 0v
Pin 5 4.54v
Pin 6 4.54v
Pin 7 4.54v
Pin 8 9.07v

IC2 (TL072CN)
Pin 1 4.55v
Pin2 4.55v
Pin 3 4.55v
Pin 4 0v
Pin 5 4.54v
Pin 6 4.54v
Pin 7 4.54v
Pin 8 9.07v

Not sure if this is the “correct” way to measure the pin voltages, but I’m putting the black lead of my multimeter on the center lug of the switch (which I believe is ground), and then the red lead on each pin.

Any thoughts?

 

[music6000]

Here is Resistor Calculator, Click on Bands for 5 colours:

Resistor Calculator

Resistor Calculator is an App developed by CherryJourney to help the user find the value of a resistor.

resistor.cherryjourney.pt

 

[pdfermat]

Here is Resistor Calculator, Click on Bands for 5 colours:

Resistor Calculator

Resistor Calculator is an App developed by CherryJourney to help the user find the value of a resistor.

resistor.cherryjourney.pt

Thanks and good catch - I de-soldered and replaced it with the correct value, but still no joy.

My god though - how did you catch that by just looking at the bands and build docs?? It’s like Neo looking at the code in the Matrix!!

 

[music6000]

I can't see all the colour bands so use the Resistor calculator link to check all your other resistors.
Have you got a 4558 that you can try in the TL072 position to see if that changes anything?

 

[pdfermat]

I can't see all the colour bands so use the Resistor calculator link to check all your other resistors.
Have you got a 4558 that you can try in the TL072 position to see if that changes anything?

Ok - I’ll give all those resistors a once-over.

I swapped out the 72 for a 4558 and no change - pin voltages also stayed the same.

 

[szukalski]

Time to break out the audio probe.

 

[jwin615]

Are all of the IC pins soldered? Hard to tell from pic.
Also, it's advisable not to trim your leads flush. You could be damaging the bond of the solder or the pad on the board. Shoot for trimming just above your fillet

+1 on the audio probe.
I'd start with just hitting a few points like these(highlighted in red). That breaks the circuit into pieces and checks all active electronics at the same time.
If also do a resistance check on your 3pdt to make sure it's properly switching all 3 poles.

 

[Lytt Effects]

Occam’s Razor? Im guessing you did, but did you make sure to turn the volume and drive knobs clockwise? If so, next step would be double-checking the polarity on electrolytic caps, but they look ok based on the build docs. After that, it’s audio probe time.

 

[pdfermat]

Many thanks everyone - it’s up and running. After I fashioned my 1st audio probe and was confident I was using it correctly, lo and behold - no signal from R1, so I figured it had to be some wiring with the breakout board or switch. I think I got too overzealous soldering the breakout board on the switch, and flowed some solder down below that caused a short.

Which begs the question - how zealous is zealous enough when soldering the breakout board to the switch? I assume too little solder can be equally bad - so what does the “Goldilocks” amount look like?

Thanks again everyone - you helped me turn a potentially very frustrating failure into a good hands-on learning experience in troubleshooting.

 

[music6000]

I was leanining towards the 4 wires going into the Main PCB from the Footswitch as the joints loked a bit lumpy so to speak.
When soldering the Footswitch, I solder the centre pad first so you can centralize.
Then solder the 4 corners so heat is kept to a minimum, wait for it to cool for 30 seconds.
Then solder the remaining 4 in between so the switch internals don't get too much heat.
You need a hot iron that solders as quick that is easy to handle, I use a Weller style 40 watt.
As soon as the Breakout pad is flush with solder, Stop!

Glad you got it working!

 

[Nostradoomus]

The footswitch is the only part I use flux on to help speed things up and improve the connection.