Film-Tech Forum ARCHIVE: ALD emitter causing hum

This is topic ALD emitter causing hum in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Dominic Espinosa (Member # 2122) on 11-29-2007, 07:44 PM:

Hey everybody...

Have a UPC series assisted listening emitter from Ultra Stereo that introduces a 60 cycle hum into the center amp (it's connected on the barrier strip input on the amp).

When the power to the emitter is cut the hum goes away.
With the help of the fine folks at USL I found that there was no ground line from the wall wart to the emitter chassis which they said would cause this issue.
So I ran a new ground for it.

No dice, the problem persists. What's interesting though is the hum is only present when the processor is switched to film sound.
In non-sync there's no hum.

Any ideas?

Posted by Gordon McLeod (Member # 33) on 11-29-2007, 07:47 PM:

Try lifting the low side of the cable
I usualyy connect them to the monitors HI output since they then get a summed signal of all channels if the monitor provides one

Posted by Dominic Espinosa (Member # 2122) on 11-29-2007, 08:49 PM:

Gordon: I connected the unit to the MONO OUT on the MS-100 yet still do not have signal.
The manual is unclear as to whether or not the processor out is required to be connected for this output to be live?

EDIT: Answered my own question on that one...Works like a champ!

Thank you, G-man!