Carvin Pro Bass II schematic needed

rust_preacher · #1 05-11-2011, 04:59 AM

A friend brought me a Carvin Pro Bass II that had been sitting in storage for a long time. The fuse blows on power switch "on". I changed the large filter caps just to start with but the problem persists. This will be difficult to troubleshoot without a schematic. The problem is clearly in the power section, as I disconnected every lead going away from it and it still blows the fuse. The transformer is OK as it retains the AC voltage when it is disconnected from the power section.

So, if anyone has a lead about where to get a schematic, I would be grateful.

BassmanPaul · #2 05-11-2011, 10:10 AM

Only one place to get Carvin schematics and that's Carvin. They've always sent me what I asked them for.

Why did you replace the filter caps? If the problem is in the power supply, diagnosing the problem is Servicing 101. Do you not have a multimeter?

Bass_Pounder · #3 05-11-2011, 10:17 AM

Done

http://www.carvinservice.com/crg/sch...sII-scheme.jpg

BassmanPaul · #4 05-11-2011, 10:24 AM

That does not show the power supply and output stage. Just the low level signal circuitry.

I'll bet the outputs are blown.

rust_preacher · #5 05-12-2011, 12:54 AM

Quote:

Originally Posted by BassmanPaul

Only one place to get Carvin schematics and that's Carvin. They've always sent me what I asked them for.

Why did you replace the filter caps? If the problem is in the power supply, diagnosing the problem is Servicing 101. Do you not have a multimeter?

It's pretty tough to diagnose a problem somewhere where the fuse blows immediately when the power section is connected. The caps looked a bit on the plump side so I thought they were suspect, that's why I replaced them (and because I have found that to be a common cause for problems before). I just don't want to go any further without a schematic.

In another post it was suggested that the output is blown which is possible. The power section and the output are in the same module, so this is also difficult to isolate since you can only diagnose the output when power is on...

I will contact Carvin and hope to be able to get support from there.

Thanks for all the help everyone.