Film-Tech Forum ARCHIVE: Dolby CP55 Fault

This is topic Dolby CP55 Fault in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Michael Harlow (Member # 1353) on 09-06-2004, 06:25 AM:

Gents,
My CP55 has developed a fault where by powering up at the start of the day it remains in bypass mode, after a while (10mins or so) it will revert to normal operation. It has gone to bypass mode a couple of times during a show. I have replaced the 3 relays on the back of the unit and also reseated all of the cards. Any ideas before I call for help? Thank you
Michael.

Posted by Steve Guttag (Member # 268) on 09-06-2004, 07:32 AM:

Upgrade your Cat 249 to a Cat 249A. This is the power regulator card. If you have more than one CP55 (or CP65)...swap the Cat. 249 and see if the problem moves.

Steve

Posted by Michael Schaffer (Member # 1204) on 09-06-2004, 06:49 PM:

We had a similar problem recently with a CP65. One of the cards (Cat.No.250) had not been properly seated. Reseating them seemed to cure the problem at first, but it turned out that the connector on the backplane had been slightly damaged by the bad contact, so I exchanged the backplane. The r/e wasn't too expensive - a little more than $200 - better than losing sound on a Saturday night.