HELP: off board wiring for ProCo RAT

[XXISouthpaw]

Hi folks, having a bit of bother trying to figure out the ins and outs of my rat pedal.
Received it none working, swapped the IC and R1 out as it was charred and started removing the 3PDT before it went into a box for over a year, and am now struggling to find a schematic that matches up properly, can anyone help with the offboard wiring or point me in the right direction to a schematic?




Red dots are where the wire traces come from, assumingly for grounds, power in and the like. I'm a bit rusty with reading pcbs so go easy on me!

Thanks in advance, this forum's the best.

Southpaw.

[GGBB]

There are multiple pads for some of the connections on that PCB. I've marked the ones that are typically used below (as they are in mine - but my PCB is a slightly different revision). Note that the white wire you have connected near C11 is the same connection - PCB IN - as the bare wire I've marked above the center switch hole.




You can sort of see the connections here - notice the bare wires connected to the top left and middle and bottom right lugs which correspond to gnd, pcb in, and pcb out respectively:




Here's the switching diagram - note the switch is rotated 90 degrees from the usual as is typically done in the RAT:

[XXISouthpaw]

Thanks so much for that! Really appreciate it.

I'd love to delve a bit more into the circuit and potentially modify it, found plenty resources for it, but do you know a source for this schematic, or can you tell me how different it is to this one?

https://www.electrosmash.com/images/tech/pro-co-rat/pro-co-rat-schematic-parts.jpg

[GGBB]

The RAT circuit has always been almost the same throughout its history. The only changes have been for adding a status LED (using a DPDT switch with a circuit that has become commonly know as "RAT-bypass"), for the Turbo and You Dirty RATs, and most recently for the FAT RAT. There were also a few very minor changes early on, and Chinese RATs use a slightly different value for the tone filter cap. This is for the production RAT - you will come across RAT schematics online that have an extra JFET input buffer - those are - to the best of my knowledge - the early "Bud Box" RAT prototypes only a handful or two of which were made (most likely by hand). The electrosmash link is for the classic RAT circuit that you would have found in later "big-box filter" RATs and whiteface and early blackface smallbox RATs (not RAT2 which added the LED). And it is almost accurate (R7 and C6 order is reversed, R7 value should be 1k6, R1 should not be present - none of which make any real difference in sound).

The most complete RAT circuit reference excluding FAT RAT - if I do say so myself - is by yours truly:


https://www.aronnelson.com/gallery/main.php/v/diyuser/GGBB/Multi-RAT.png.html