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Combo 300 problem...

Discussion in 'Amps and Cabs [BG]' started by georgestrings, Jan 9, 2006.


  1. georgestrings

    georgestrings Banned

    Nov 5, 2005
    I'm looking at a Peavey Combo 300, that has something wrong with it - here's the symptoms:


    The 1st time I played it, it powered up just fine, and sounded very good until I started turning it up - then it started breaking up as I approached approx. half volume... I hooked it up a known good cab to it, and it still did the same thing, so that eliminates the speaker as the problem, IMO...

    The next day, I looked at it again, and it would power up, but wouldn't put anything out at all...


    Does this sound like it could be a power transformer crapping out, or is it likely something else??? I'm figuring that if it's anything OTHER than the trans, I'll be able to fix it fairly cheaply, and make out in the deal... If all fails, it has a healthy 15" Black Widow in it that's worth what they're asking for the thing - so it's worth it, if only as a 15" cab...


    How about it, amp gurus - any thoughts???

    I'm thinking either a cold solder joint, a bad connection somewhere, or a fairly non-expensive component that I can replace myself(I have a small background in electronics)... I've never had to replace a power transformer in an amp, so I don't know what they act like when they crap out...



    - georgestrings
     
  2. The only time I had a problem with it (about ten years ago) I wound up having to replace the master circuit fuse. That fuse has now lasted ten years with no issues. I would try that before anything else (even if it seems not to have blown).

    Jay
     
  3. georgestrings

    georgestrings Banned

    Nov 5, 2005

    Jay - I played through one for over 10 years, and during that time - the only time I ever had a problem with that one, a break developed in a shunt, which in turn caused a capacitor to burn to a crisp... I fixed the break in the shunt, replaced the cap(total cost about $2), cleaned everything up - and it continued to give me trouble-free service until I sold it, years later... I still regret selling that amp, so I'm trying to bargain my way into another one, as a "spare" to my main rig - and just because it'd be handy to have around, and would sound great with my recently aquired 410TXF, should I decide to use it that way...


    That being said, I'll still check out the fuse, as you mentioned - thanks for your input...



    - georgestrings