Bauer 502 noisy amplifier

[David Roberts]

Have just obtained this projector,and on testing,the amplifier is noisy,a sort of rustling sound like being in a storm!
It can be used,but on quiet bits,there is more noise than there should be.
Any ideas please? .Otherwise,a good machine with very quiet shutter cam and steady picture.
Ive tried the record button trick, but hasnt improved things.
Thanks.

[John Burgess]

Hi David
Sounds like a capacitor on the way out, or may be a dry joint in the circuitry. Have you opened it up to see whether there is anything obvious, lose wire etc. You could try some switch cleaner on the pots.These are always tricky ones to identify.
Good luck John

[John Armer]

I had the exact same problem with my Eumig S940 which was completely solved by swapping out the bigger capacitors, so I would agree with John on this one. They must be 40 years old now and high time for replacement. Van Eck offer a kit I believe ( https://van-eck.net/en/product/bauer...pare_part_kit/ ) with replacement caps for these projectors if you want it easy to find replacements.

[David Roberts]

Thankyou both Johns.
I have just replaced the 3 larger capacitors on the main board but no change.
I will delve deeper,
Thanks again.

[Maurice Leakey]

,,,,,May be a dry joint in the circuitry....

I quite agree with John.
Many years ago I had nasty noises in the amplifier of my newly acquired Elmo GS-1200.
My engineer (at the time) discovered so many dry joints that he removed the old solder from all the joints and applied new solder to each joint. It took some but it completely cured the problem.
Regrettably all our beloved projectors are now getting old in the tooth.

[Dave Bickford]

My Sankyos are the same. I’m going to find somebody to recap the PCBs.

[Brian Fretwell]

Also a dirty track on the volume control can cause this either replace or use compressed air spray to try to clean.

[David Roberts]

Thanks for all the suggestions.Will report back when sorted.