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Hope everyone is enjoying their Sunday! Only a little trouble actually but couldn’t resist the pun. First of all this muff is going in a box with a rat and a model t preamp. Only the muff and the rat are hooked up now as I’m waiting for parts that I didn’t order initially. I am getting almost no volume out of this circuit. All the mods seem to be working properly but I had to put my soulfood bass in front of it to be able to test this. I’m pretty sure I will be asked to provide values on the four transistors but I don’t know how to do this. I’m a total noob and this is my first from parts build (industrial fuzz from ppk works great). I’m having some issues with the rat as well but I do not have the correct transistor and will replace that before going into that(I found one that works in a grab bag of parts a buddy gave me). By the way easy switch seems to work great and I have a multimeter but I’m just scratching the surface of its uses. Thanks guys.
Ideally it is best to test each circuit on their own to rule out other issues.
So if you did not do this first I suggest carefully holding an iron to the pads (one at a time) on the Easy Order switching board and removing the wires so you can test the Muff’n by itself.
This will leave a bit of solder in the pad but that is fine. Simply reheat the pad and push the wire back in after solving the issue. (with some careful finger dexterity and wizardry).
If the problems are identical double check off-board wiring and fix or re-flow where needed.
If you are still having issue then test each transistor by itself with your DMM
Put the DMM on V or volts (DC).
Put the black probe on any ground of the board or wiring. Put the red probe on each pin of the transistor and record the reading.
List them here in a format that is easy to read like:
Q1:
E:
B:
C:
Thank you. I had originally placed the transistors without sockets because I didn’t have any. I removed them earlier today and installed sockets and new transistors. I also reflowed all off board connections. Now I have removed the easy switch from the equation and there is no change. Transistors read as follows.
Q1 e .068
B ..622
C 7.22
Q2 e .043
B .592
C 7.62
Q3 e .039
B .585
C 7.76
Q4 e .237
B .789
C 8.10May just be the light but your 100K resistors R9, 14 and 21 look like they have a grey band instead of orange as I say might just be reflecting light
Your transistor voltages are way off are you sure they’re correctly orientated is it 2N5088s you’re using
Also, from the build notes beneath the BOM page:
“You can use the higher gain 2N5088, but you must put a ~33K resistor in R25.”
I have bc549c transistors. I’m doing the green Russian version. I should probably have mentioned the variant. I’ll take a look at those resistors. Maybe not tonight, I got heat stroke today so probably wont be hunched over my desk tonight. Thanks guys.
Oh my god. That’s really embarrassing. The transistors were in backwards. After all the times I’ve read to check that and honestly I thought I had. They do say if everything works the first time you don’t learn anything so I guess I have been educated. Thanks guys!!! I know I’ll have more issues to go over soon.
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