PURP has no sound when turned on.

[Angry Badger]

I’m new to building. Just did a pumped up rangemaster kit. Bypass works. LED turns on when engaged but pedal has no sound when turned on. I get voltage to and from the board and switch. I was wondering if someone could help.

[Billy]

Although its fairly difficult to see it looks like your diode D1 is the wrong way around the cathode striped side should go the other way around

Easy enough to confirm check what voltage you get on pin 8 of IC1 I’d suspect little to nothing

What may be happening is with the diode the wrong way around power will conduct through it straight to ground rather than into the circuit via IC1

 

[Barry]

D1 is in the correct orientation for v4 of the board.

 

I am looking hard at some of the solder pads that seem open. You may want to reflow your solder joints.

For example:

 

Also remove the wire from the inside of the Jack so your plug is not going to hit it when inserted.

 

Also two different Red Wires may be damaged depending on how many strands?

[Angry Badger]

1. How are the pins numbered? Also I put the gray line of the diode on the white striped side of the PCB if that helps you. I can take a better picture. How much voltage should I get and where am I measuring across? Is that from the pin to the ground or just to the other side of the diode?

[Angry Badger]

In response to Barry I tried improving the solder but I ended up making it so the led won’t even turn on anymore. Should I just get a new PCB and GPCB and redo the solder joints? I have reworked this thing so many times from taking it apart trying to locate the issue. It was soldered much better initially but now some of the wire holes are burnt and several of the wires have been nicked with the iron as you pointed out. I also have a problem of the wires fraying where they attach to the board and then breaking after reworking another part. Is that from too much heat?

[Barry]

Since it is likely damage after what you just said I absolutely believe the project is worth getting a new PCB and 3PDT to finish it.

[Billy]

Damn I checked the guides page for the latest build doc too

Guess I’ll stick to the shop docs from now on

Twice in a week

I’ll give myself a slap

[Angry Badger]

After dissembling the pedal but not the PCB it appears the damage is in the switch. Is there a way I could wire this as always on to test the pedal circuit but skip the switches? If so which wires are needed to connect to the main PCB?

 

[Angry Badger]

I would like to skip the 3pdt and the my spdt

[Angry Badger]

In my mind I would connect the audio tip to the T in and the ring to the G in. Then the same for the out. Wire 9 volt as it was, but I’m not sure about the spdt because I don’t understand what it’s doing.

[Billy]

That’s correct just wire your in and out jacks to the pcb

The spdt just puts either C2 or 3 in paralell with the input cap C1 giving you full mid and treble range

Leave that in the middle off position

[Angry Badger]

If I leave the spdt unwired for testing is that off? Or will that break the circuit?

[Billy]

Yes you can leave it out it’ll just go through C1 looking at the schematic

[Angry Badger]

Well I’ve tried to isolate the board and I can’t get anything but buzz. I have voltage across the wires. The resistors are all measuring what they should. I have varied resistance as expected across the pot. I just can’t get it to work. i cleaned the board and checked solder joints too.

[Angry Badger]

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[Angry Badger]

[Barry]

This would help you identify the issue by location quickly as well as being a valuable tool for future projects.

Build an Audio Probe

[Author]

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