First build unsuccessful! Help?

[harry haggis]

Hi,

I built a 5 knob fuzz pedal using the PCB and wiring layout off of here:
http://www.musikding.de/product_info.ph ... atine.html

I put it all together, drilled out the enclosure and housed it all inside just to check there was no contacts touching that shouldn't be but I get nothing when tested. No LED, no signal, using a battery or 9v power supply.

What's the best next step? Should I disassemble everything (assuming the PCB is all good) and try re-assmebling the pots/switch and inputs?

I'm a little unclear about using a multimeter/audio probe to tesdt the circuit.. I have a multimeter but didnj't checlk the PCB as I was going.. and also got confused as to how I would test all my connections.. as it includes resistors, transistors and diodes etc.. how would I use a multimeter to check this circuit and get it working? Or is it an audio probe I need?

Thanks!

[DrNomis]

Hi,

I built a 5 knob fuzz pedal using the PCB and wiring layout off of here:
http://www.musikding.de/product_info.ph ... atine.html

I put it all together, drilled out the enclosure and housed it all inside just to check there was no contacts touching that shouldn't be but I get nothing when tested. No LED, no signal, using a battery or 9v power supply.

What's the best next step? Should I disassemble everything (assuming the PCB is all good) and try re-assmebling the pots/switch and inputs?

I'm a little unclear about using a multimeter/audio probe to tesdt the circuit.. I have a multimeter but didnj't checlk the PCB as I was going.. and also got confused as to how I would test all my connections.. as it includes resistors, transistors and diodes etc.. how would I use a multimeter to check this circuit and get it working? Or is it an audio probe I need?

Thanks!

The next thing I would do is use the multimeter to check the voltages in the circuit, to do that you need to set the multimeter to read DC Volts, then you need to work out if the circuit ground is positive or negative, if positive connect the red multimeter to circuit ground, if negative connect the black multimeter probe to circuit ground, next touch the other probe to the collector terminals of each of the transistors and note the readings you get and compare them to what's given in the schematic, for the common supply rail you should see 9V (assuming the pedal is powered by a 9V battery)....

[harry haggis]

Thanks for that! I have a few questions about it, howdo I test to see if the ground is positive or negative? I assumed all grounds were negative?

I've used this PCB: http://www.musikding.de/product_info.ph ... z-kit.html

Thus I've used the illustrations on the circuit board to determine which way round my transistors go.. How do I tell which is the collector? and which note on the schematic relates to what I should be reading off the multimeter?

http://diy.musikding.de/images/stories/ ... schalt.pdf

And by common supply rail I assume you mean touch one side of the Multimeter to ground and one to the positive point of the battery clip/power supply? to see what it reads?

Thanks!