Guy at work that is into old movies on film asked me about hum in a movie projector and how to cure it.
I'm assuming that the filter capacitor(s) in the power supply is the issue but then I don't play with audio much.
Any tips on troubleshooting? It uses transistors, no tubes.
Thanks,
Wes
Hi Wes, Lets bring your post up to rec.antiques.radio+phono.
Tom
projector and
then I
If it uses an optical track make sure no room light is reaching the photoiode. If you have a scope, look at the voltage feeding the exciter lamp. They are either DC, or above 20 KHz. Any ripple on that supply will be detected and amplified.
Thanks Mike. Tom, I can't reply to your suggestion since agent won't download your message. Something with easy news. I'll keep your newsgroup suggestion in mind though. Since the guy at work hasn't contacted me, I'm assuming he may not have bought it.
Thanks all,
Wes
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