Film-Tech Forum ARCHIVE: CP55/65 Bad CAT 249 cards

This is topic CP55/65 Bad CAT 249 cards in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Trevor Meusx (Member # 10737) on 01-20-2019, 06:54 PM:

When the 249 voltage regulator cards go bad we've noticed this god awfully loud humming that goes away after 20 minutes or so from powering on. Over time it stops going away all together, but does anyone know what faults in these cards to cause this? My first inclination is bad caps. I'd appreciate anyone who can shed light on this with their experience. Take care!

Posted by Tony Bandiera Jr (Member # 2365) on 01-20-2019, 11:33 PM:

Yep, most likely bad caps. Best to get them changed asap, running with them in that condition can lead to a failure that can wipe out other cards in the processor.

At the age of those processors, it is not surprising to have that happening.

Oh, and welcome to Film-Tech. [Big Grin]

Posted by Trevor Meusx (Member # 10737) on 01-20-2019, 11:52 PM:

Thanks Tony! For the 411 and a warm welcome. [beer]

Posted by Gordon McLeod (Member # 33) on 01-21-2019, 08:33 AM:

Replace the capacitors and the regulators on them and they should be good to go for years Also check the actual enclosed powersupply

Posted by Mark Gulbrandsen (Member # 72) on 01-21-2019, 12:07 PM:

Only the power transformer, voltage select switch, power switch and fuses are in the main CP-55 power module, unlike the CP-50 where it's also home to bridge rectifiers and more capacitors. The are cat 249a's available on EBay, or you could write to Sam Chavez at Bay Area Cinema Products and see if he has any 249's available. Sam is handling card repairs and sales on the older Dolby processors.

Mark