BIG MUFF PI not working

[jan007magic]

hey guys, I built a Big Muff Pi (green russian) with Rams Head PCB layout, followed everything on the layout but it didn't work..

I used a 2N3904 instead of a 2N5088, all mylar caps except for the 470pf's which are ceramic.

the transistors did not get hot when I plugged it in.

thanks!

[Elijah-Baley]

When you get a "not working building" the problems are the usual.

You should search for some debugging methods.

Meanwhile, can you give us more details? Did you get any sounds? Are you testing just the circuit or are you connected the footswitch already?

First check: read the pinout of your transistors datasheet (2N3904s are ok) and compare with the any big muff npn schematic, and look your pcb.

[induction]

http://www.diystompboxes.com/smfforum/index.php?topic=29816.0

[jan007magic]

input and output are directly connected

layout


schematic


build

[GibsonGM]

No dude, the input is where it says "SW 1a".  What you're seeing is the power switching - where your input jack switches the power on and off when you insert/remove it.  That part of the jack isn't connected to anything audio, so it's not part of the signal path.

On the first page of the build your own stompbox forum, there is a sticky post called DEBUGGING.   Read it, try to provide the info, and people will be able to tell you what to do.   Shooting in the dark is a waste of time, don't do it.   You probably need an AUDIO PROBE (search), which would tell you a LOT in a short time...

[hymenoptera]

oh my. How do you plan on getting those pots through their holes in the enclosure? They're pointing in 3 different directions! 

[jan007magic]

I know where to put the input and output and the power, I just didn't installed the  footswitch