[sdiy] Damned amplifier

[harrybissell]

and I would check for interstage coupling electrolytics, which do just
this
sort of thing. The clue is to look for wrong / varying DC levels in
stages
working back from the output.

I had a Marantz amp that would go @pesh!t when the drummer hit just ONE
particular tom... then work perfectly otherwise. Turned out to be a lead
broken
off the end of an axial electrolytic coupling cap... the remaining lead
and body
of the cap were PERFECTLY resonant at that frequency... boom boom SPLAT!

Also try some freeze mist, or heat gun to find thermal intermittants.

H^) harry

epeasant at telusplanet.net wrote:

> I would check the pc board for cold solder joints,
> especially where connectors and controls or large parts are
> mounted.
>
> Take care,
> Doug
> ______________________
> The Electronic Peasant
>
> www.electronicpeasant.com
>
> > today my stereo amplifier developed the same problem!
> >
> > sounds like crackling on the left side. I took it apart,
> > cleaned it. the
> > problem was gone. I put it all back together, then 5
> > minutes later it
> > returned!!!!!
> >
> > I'm open to ideas. I thought maybe the caps in the power
> > supply were
> > dead. Am I crazy?
> >
> > mark
> >
> > Glen wrote:
> >
> > >At 03:06 PM 11/11/02 , Linium wrote:
> > >
> > >>Hello,
> > >>
> > >>I have 2 stereo amplifiers that show almost the same
> > faulty behaviors and i
> > >>would like to ask about this kind of problem.
> > >>
> > >>The amplifier work ok but there are some moments where
> > a voice start to have
> > >>some very short loss in the signal, like there is a bad
> > contact somewhere.
> > >>
> > >
> > >Do the amplifiers use relays to delay the amplifier's
> > connection to
> > >speakers, as a means of preventing "turn-on thump"? If
> > so, these relays can
> > >develop poor connections and cause problems similar to
> > what you describe.
> > >They can also cause crossover distortion.
> > >
> > >later,
> > >Glen Berry
> > >
> >
> >
> >