VintageKustom.com: Repairing Kustom Amps

Home » VintageKustom.com » Repairing Kustom Amps » Help with a K200B

Show: Today's Messages :: Polls :: Message Navigator

Help with a K200B [message #8443]

Mon, 19 March 2007 15:52

Forge
Messages: 41
Registered: February 2005
Location: In car trunk in Danville ...

Member

I'm having some problems with my amp and was wandering if you guys could help troubleshoot

I was using my k200b head for recording; I was using the RCA DI into a Line6 Guitar Port (which by the way sounded awesome!) without the head connected to the cab. The amp still has its original power cord (no ground), in the middle of recording about every 15 min. I would get this really loud popping noise for about 10 sec. and then it would stop and be just fine. After I finished recording I hooked the cab back up and I noticed that even at half volume its really quite. I'm thinking its a problem with the pre-amp because when the amp powers up it still gives a healthy thud from the speakers but still half vol on both bright and normal sides

SO anyone knows what�s going on?

Thanks
Forge

Report message to a moderator

Re: Help with a K200B [message #8444 is a reply to message #8443]

Tue, 20 March 2007 06:45

stevem
Messages: 4886
Registered: June 2004
Location: NY

Senior Member

Well this is a strange one due to the fact that the RCA jack you where feeding out of is driven off of transistor Q700 the first gain stage on the amps PC 703 driver board, so if your reconding level did not change while recording, than Q703 must be OK.
There are three other transistors after that before the main power output stage, and like you said if your getting a good thump at turn on than chances are that stage is good, which leaves those three transistors,Q701 Q702 Q703.
There is a coupling cap that feeds that record jack so I dought that any stray damaging DC voltage got back into the Kustom from the other item of gear you where running thru.Just for kicks, if you have a ohm meter, set it for continuity or ohms, and make sure that the RCA jack is not shorted for some strange reason.
Other than that I would supect Q701 OR Q702 to be to blame.
Let us know how it goes!

Report message to a moderator

Previous Topic:	3-15s
Next Topic:	Identifying/repairing

Goto Forum:

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

]

Current Time: Tue Jul 14 15:50:14 EDT 2026