"Greg" bravely wrote to "All" (22 Aug 04 09:31:02)
--- on the heady topic of "Pioneer SX-9000 Problems"

Gr From: Greg

Gr Hi,

Gr I recently came into possession of a 1970 Pioneer SX-9000 receiver.
Gr While trying it out I found that when changing the volume a loud
Gr crackling sound was coming out of the speakers. I researched the
Gr issue and found it was most likely due to dirty contacts, I tried
Gr some tuner spray but it didn't do anything. I also noticed a hissing
Gr sound coming out of the speakers when no music was being played and a
Gr "clunk" noise when turning the unit off. At this point, I contacted a
Gr local electronics repair shop and took it in for an estimate. They
Gr gave me an estimate to clean the contacts and replace a few capacitors
Gr that were bad. Well, I picked up the unit yesterday and 95% of
Gr cracking is gone and no more clunking happens when powering the unit
Gr off. However, the hiss remains. In the google archives, I found the
Gr following:

Gr http://groups.google.com/groups?q=pi...l=en&lr=&ie=UT
Gr F-8&selm=d2e5798e.0203062230.7339362e%40posting.goog le.com&rnum=1

Gr The problems outlined in this post are mostly what is happening to
Gr mine. The one thing I can add is the hissing gets much worse in one
Gr channel as the receiver warms up. Within 15 minutes, the hiss becomes
Gr noticeable and starts to degrade the sound of the music coming out of
Gr that channel.

Gr Any suggestions on what I should do to fix this? The above repairs
Gr already cost me $65 and I don't want to put much more money in to
Gr this. My electronics skills are minimal (I can solder a bit), so if I
Gr knew exactly where the problem was I could try to fix it myself.
Gr Also, do I have a beef with the repair shop?

Gr Any advice and suggestions would be helpful.

Gr Thanks,

Greg, the shop didn't do a very thorough job but then again this type
of restoration work isn't very cost effective from their viewpoint, so
I can't really blame them as it probably cost them more than the $65
in time alone. I'm afraid a 70's receiver is a nicely complex piece of
equipment. However, you might try to narrow down the problem as to the
tuner or the audio circuitry. One question is, does the hiss exist only
in FM or also in AM or when set to AUX, or when the volume is at zero?

A+s+i+m+o+v

.... 'Keep the smoke inside.' -- 1st Rule of Electronics.