Film-Tech Forum ARCHIVE: Cat.700 power supply humming

This is topic Cat.700 power supply humming in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Michael Schaffer (Member # 1204) on 07-07-2004, 05:09 AM:

I just had 2 of these fail, one could be saved by soldering the wires which had blackened in the infamous molex connector directly to the board. After the same operation, the other works now too, but it still makes a loud buzzing sound. I couldn`t locate which of the parts on the board makes it. According to the projectionist it started smoking at one point, but there is no visible damage. Both the humming and the smoking were apparently there before the operation.

Posted by Darryl Spicer (Member # 711) on 07-07-2004, 09:29 AM:

Sounds like it could be a transformer issue within the power supply but that is just a thought. Would have to take it apart and see where the smoke and hum could be coming from.

Posted by Mark Gulbrandsen (Member # 72) on 07-08-2004, 12:02 AM:

Oh no! You didn't let the smoke out???? Now ya got to get it back into where it came from. How ya goin to do that? Joe wants to know..... [Confused]

The P.S. doesn't use a transformer per say since its a switching supply and runs at high frequency.

Mark

Posted by Gordon McLeod (Member # 33) on 07-08-2004, 09:06 AM:

I thought in california you were not allowed to smoke indoors anymore [Big Grin]

Posted by Darryl Spicer (Member # 711) on 07-08-2004, 12:57 PM:

Jesus, does anyone have any real answers to his problems. If not then I guess you should call Dolby and ask their advice.

Oh and smoking is banned inside public buildings in our city. [Smile]

Posted by Mark Gulbrandsen (Member # 72) on 07-08-2004, 08:58 PM:

Its TTRI for that power supply... best known as Time To Replace It.

Mark

Posted by Michael Schaffer (Member # 1204) on 07-09-2004, 02:12 AM:

I ordered a repair exchange since it looks like it isn`t a part that would be easy to isolate and desolder on my kitchen table. In the heat of the summer season, we don`t want to go without digital for too long.