Right, first of all, can you just reply to this thread or its going to get very confusing reading a new thread every step.

Second, you need to take the voltages with the transistors in, set the multimeter to the 20V range setting, stick the black probe on the enclosure (a screw hole makes a nice anchor) and use the red probe to measure each transistors 3 pins and put the voltages up for each one, like this;

Transistor 1
C (collector) 2V
B (base) 0.6V
E (emitter) 0V

Transistor 2… etc.

Hmm, definitely something not right, your voltages are way off, transistor one should have ground on its emitter.

Does your meter have a continuity setting? It’ll probably be paired with the diode checker and have a little o))) symbol, if so, set the meter to that and put one lead on to the enclosure and one on to the ground point on the board to make sure it’s connected, if it is it should beep.

Are you sure you put the new battery snap on the right way round too? If you reversed the polarity that would be a problem.

Sorry for the delay in reply.

Ah, right I see whats happened, the voltages are ‘right’ but they’re just inverted as it’s positive ground so they actually read like this;

Transistor 1

C = 9.15
B = 1.81
E = 1.26

Transistor 2

C = 1.81
B = 0.58
E = 0

Which is in range so the circuit should be functioning.

So, time to investigate the switch, as you say you have no continuity tester on your meter we’ll have to do it with resistance, so first off take the battery out and put your meter on to the ohms setting.
Then you see the switch has 2 rows of 3 lugs, put your probe common on the center lug of one row and the other lead to the lug to the left of it, it should read either (near) infinite or (near) zero resistance, then slide the switch to the other position and it should read the opposite of the first test (so if you measured infinite first it should now read zero after sliding the switch and vice versa).
Then while keeping the probe common on the center lug put the other lead to the lug to the right of it and repeat the test, do this for both rows.

Report back with how you got on and then it might be time to build an audio probe.

Okay, next step then is an audio probe, here is a guide to building one and how to use one, it’s quite simple and should get to the bottom of where the problem is.

http://www.diystompboxes.com/wiki/index.php?title=Debugging

And the schematic to work from;

Test at the base and collector of each transistor and describe what you hear.

Hi Paul,

No a buzzer wont be any good, the point of the audio probe is that you can hear exactly what is happening to the signal at different points in the circuit, so if you probed the input transistor base and there was nothing or a very weak signal you could assume there’s a bad connection from the input jack or a short somewhere and if you probed the second transistors collector and there was no boosting happening you’d know the issue was between the transistors etc.

And yes the 9V battery needs to be installed and the circuit switched on with some kind of signal being put through the circuit (strumming a guitar, a CD player or whatever) when probing.