VintageKustom.com
VintageKustom.com is your source for literature and information on the tuck-and-roll vintage Kustom amps from the 60's and 70's, as well as their related products such as guitars and organs . We provide a webboard for help with kustom gear history, technical information and repairs as well as discussions with other collectors.

Home » VintageKustom.com » Repairing Kustom Amps » K-250 (hum on first channel only)
Show: Today's Messages :: Polls :: Message Navigator
Switch to threaded view of this topic Create a new topic Submit Reply
K-250 [message #22342] Tue, 03 February 2015 17:15 Go to next message
Iowa Boy is currently offline  Iowa Boy
Messages: 767
Registered: June 2014
Senior Member
Need some tech advise guys. I'm checking out an amp that one of the guys on here was looking at possibly buying. I contacted the owner and he says theirs a hum on the first channel but not the second channel. He's had the pots cleaned and says the filter caps are okay and still is using the original power cord. Any idea's were the problem is at and is it an easy fix? Thanks.

I did read the earlier thread on here about the other K-250 that had issues so I do understand where the problem might be coming from was just hoping someone might know the immediate cause.

[Updated on: Tue, 03 February 2015 18:31]

Report message to a moderator

Re: K-250 [message #22344 is a reply to message #22342] Wed, 04 February 2015 00:06 Go to previous messageGo to next message
Kustom_Bart is currently offline  Kustom_Bart
Messages: 601
Registered: October 2010
Location: Greenville, MichiGUN
Senior Member
Not a tech, but I can usually track down what is bad. You can fix anything and I had one that was weak on one side and it was just a resistor and took my guy about 5 minutes to install a new one. There isn't anything on these that is expensive to fix, just remember not to get carried away and start replacing things that don't need to be replaced. If it isn't bad don't mess with it Smile I have a few kustoms that have never been messed with and they still sound great. The guys on here that are tech savey can get you hooked right up. They are super smart on this stuff. I am just smart enough to take a meter and start probing until I find a blown or weak part.
Re: K-250 [message #22346 is a reply to message #22342] Wed, 04 February 2015 00:59 Go to previous messageGo to next message
chicagobill
Messages: 2006
Registered: April 2003
Senior Member
A hum could be caused by any number of things, loose wire, dirty socket connector, bad opamp, etc. Because it only effects one channel, it shouldn't be that hard or expensive to fix.

There are also different kinds of hum, that could help in identifying the problem.
Re: K-250 [message #22348 is a reply to message #22342] Wed, 04 February 2015 06:44 Go to previous message
stevem is currently offline  stevem
Messages: 4774
Registered: June 2004
Location: NY
Senior Member
It could be something as easy as cleaning the switch contacts on that channels input jacks so that they short out to cancel hum as they should when nothing is plugged into them!
  Switch to threaded view of this topic Create a new topic Submit Reply
Previous Topic: K150-8 smoking...help please
Next Topic: dc voltage at the output
Goto Forum:
  

-=] Back to Top [=-
[ Syndicate this forum (XML) ] [ RSS ]

Current Time: Wed Nov 06 08:26:09 EST 2024