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bigmike
 
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Default static on right channel of kenwood receiver


"Sharon Leigh" wrote in message
...
Thanks, Mike, I will try that. I am trying to learn more about audio
electronics (I haven't touched an oscilloscope or ohmmeter in about eight
years, since my days in computer school), but I fear I don't have the
patience for big problems...


I understand. The one thing in your favor is those old Kenwood amps were
built well. If you decide to give it a go, let us know, and we will try to
help you further...

"bigmike" wrote in message
m...
I meant to say tap on the board lightly, not tap on the board lighting



"bigmike" wrote in message news:...

"Sharon Leigh" wrote in message
...
I have done a pretty thorough visual inspection. Don't see any bad

solder
at
the speaker terminals. No obvious burn marks or smells. I really

don't
think
the receiver is worth the effort to fix unless it's something fairly
simple,
which it apparently isn't. I am, however, going to go through the

boards
one
more time with a magnifying glass to see if there's something I

missed.

Thanks for your help everyone.

Most of the time, a problem like this has no visual indications. A
transistor or cap can be defective without any outward signs of a

problem.
Something you might want to try is tapping on the board lighting with

the
end of something plastic, like the reverse end of an ink pin, while

the
amp
is on. See if you hear the noise problem change. A bad solder joint

could
be
just about anywhere on the board, not just at the speaker connections,

and
cause the problem. If you have limited abilities at troubleshooting,

then
it's true, you will have to make a judgement call on whether it's

worth
repairing or not. But, if your interested in learning more about
electronics, this amp would make a nice place to start.




"bigmike" wrote in message
m...

"Sharon Leigh" wrote in message
...
Yes, I swapped speakers. I also moved the set over to the B

speaker
terminals. Guess what? Same problem.

Then it's time to start trouble shooting. No particular "common

part"
is
the cause of that problem. Any switch on the front of that unit

can
have
dirty contacts and cause static. Be sure to try them all to see if

they
have
an effect, including the tone controls. They all have seperate

contacts
for
each channel. If it's not the switches, then I would check the

board
for
any
bad solder joints. After that, it requires basic troubleshooting

skills,
a
few basic pieces of test gear, and some basic electronic skills.

By
the
way,
what does this static sound like? Is it like a hiss, or is it a

frying
sound? A frying sound tend to point one toward a bad

transistor(s)
in
the
output stage. Maybe you could explain the sound a little better.


"Jeff" wrote in message

...
Have you swapped the speakers?
Jeff

"Sharon Leigh" wrote in message
. ..
Yes, I do have sound in the bad channel. I think the best

way
to
describe
it
is that it sounds like a radio station that's not tuned in
properly.
It's
staticy and garbled.
"bigmike" wrote in message
m...

"Sharon Leigh" wrote in message
. ..
I was just reading the post about the marantz receiver

static
problem.
Mine's slightly different, in that it goes away when I

turn
the
balance
all
the way left, and my headphones work fine. I cleaned

every
conceivable
contact and circuit and still have the static. The

receiver's
32
years
old
so I am suspecting something has died or fried along the

way.
anyone
have
any ideas?


Lot's of possibilities. Dirty or worn speaker switch

contacts,
bad
relay
(if the old amp uses one) contacts, dried up caps, leaky
transistors.
Headphones require very little power to produce sound, so

some
problems
in
the output stage might not show up when using them. By

the
way,
do
you
have
sound through the bad channel along with the static, or

just
static?