RAT Vero Troubleshoot

[Luke51411]

I'm working on a rat on vero from tag board effects and not getting any output thus far.
I audio probed and the signal only goes to pin 3 on the lm308. I've gone over the board numerous times to be sure that everything installed properly and soldered well with no bridges etc
The voltages are as follows

1. 0
2. 2.4
3. 4.1
4. 0
5. -.5
6. 2.5
7. 9
8. 0

Does this point to a dead chip or is something else going on here? I checked for continuity to ground on pins 1 and 8 and they aren't going to ground. The voltages seem kind of off to me... should pins 2 and 6 be that low?

Here's the board (it's part of a multi so ignore everything above the sharpie line)

Here's the layout, it's the top version
http://tagboardeffects.blogspot.com/2012/01/proco-rat.html

[bloxstompboxes]

Ummm, am I missing it? I don't see the clipping diodes.

[Luke51411]

Ummm, am I missing it? I don't see the clipping diodes.

They're on a switch. The two blue wires go to the switch they're on.

[Ben Lyman]

I don't know anything about vero, that's Latin for true or straight, isn't it? Anyway, a pic of the bottom might better help others to help you 
You know, to make sure you got cuts in the right places, around the IC and stuff.
Good luck! Rats are the best!

[idy]

Maybe a short on the stuff attached to pin 2 or 6, the feedback loop.
Too bad the chip isn't socketed.
+1 on photo of solder side.

[Luke51411]

Maybe a short on the stuff attached to pin 2 or 6, the feedback loop.
Too bad the chip isn't socketed.
+1 on photo of solder side.

Yeah I might remove the chip and throw in a socket... I'll see if I can get a good pic of the solder side, I've checked all rows for shorts to the adjacent rows with a continuity meter and didn't come up with anything. I have a working rat I guess I'll open it up and check the voltages on the chip.

[dbp512]

Check if there are any solder bridges on the other side. I just made a mutron V envelope filter, but there were 2 solder bridges that turned it into a weird analog bit crusher sound. After fixing those (about 5 seconds after the iron heated up) it worked perfectly. Maybe you did something similar which is grounding your signal, or sending it somewhere else inaccessible.

[Luke51411]

Replaced the IC and added a socket. Works now.

[bloxstompboxes]

Glad you got it working!

[Luke51411]

Glad you got it working!

Sounds great too! Hopefully will sound even better when I get it wired up in the multi I'm building, it will be going into a muff!

[LightSoundGeometry]

Glad you got it working!

Sounds great too! Hopefully will sound even better when I get it wired up in the multi I'm building, it will be going into a muff!

hey which version are you building? link it up , I want to build one, I have a 308 IC chip here at home. I see about 3-4 of them on tbfx. thanks!

[Luke51411]

Glad you got it working!

Sounds great too! Hopefully will sound even better when I get it wired up in the multi I'm building, it will be going into a muff!

hey which version are you building? link it up , I want to build one, I have a 308 IC chip here at home. I see about 3-4 of them on tbfx. thanks!

Link is at the bottom of the initial post. I built the top layout on that page.

[Luke51411]

If you meant the muff circuit, I built the Musket fuzz which is a tricked out modded muff.
http://tagboardeffects.blogspot.com/2012/02/blackout-effectors-musket-fuzz.html

[LightSoundGeometry]

right on luke

does anyone have a verified schematic?  I would like to breadboard it first , not good enough yet to trace a vero to BB ..if I weren't so busy in school, I would attempt the trace haah

[bloxstompboxes]

There are all kinds of them on line including a multi-rat scheme showing all the variants. You could also just go to a site like tonepad.com and use the schematic from the build pdf. It's good. This is the multi-rat schematic link below.

http://music-electronics-forum.com/attachments/26656d1387061571-multi-rat.png