Film-Tech Forum ARCHIVE: Kelmar TB2(?) preamp malfunction

This is topic Kelmar TB2(?) preamp malfunction in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Jeff Else (Member # 4063) on 03-25-2012, 11:29 PM:

Greetings all,
Recently, at a theatre I occasionally do projection, I experienced a curious problem. The theatre has a Kelmar TB2 LED supply/preamp (at least that's what I think it's called, it was the only writing that could be interpreted as a model number on the thing), which feeds directly into a sound board (not ideal, i know). anyhow, upon powering up, the "LED" status light lights up, however the "PRE AMP" led didn't light up for a few minutes, and no sound was output until it did. also, a few minutes after lighting and getting sound, the status led and sound faded for a moment, then popped back on and stayed on for the rest of the night. Any ideas? I'd like to avoid this getting worse/weirder and them having to cancel shows...

Thanks in advance!

Posted by Kenneth Wuepper (Member # 1174) on 03-26-2012, 07:25 AM:

Jeff,

There is a jumper on the back of the power supply that turns the supplies on and off so you can have the system powered only while the machine is running.

You might want to determine how that feature is being used (or not) to see what is going on.

Also the edge connector on the solar cell (camera/preamp card) can come loose and cause intermittent sound.