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Author Topic: CP50 center channel dropping intermittently Dominic Espinosa Phenomenal Film Handler Posts: 1172 From: Boulder Creek, CA. Registered: Jan 2004 posted 05-10-2012 09:35 PM                     Subject says it. I've got a CP55 with SR on a newer Kelmar redlight reader -- the problem existed with the old Jaxlight that WAS in here last week. It is dropping center channel intermittently. I have dialog on the Left/Right pretty clean but it comes through in crackles on the center. Definitely coming from the processor like this. Thoughts?  |  IP: Logged Richard May Phenomenal Film Handler Posts: 1057 From: Floral Park, NY USA Registered: Aug 2004 posted 05-10-2012 10:09 PM                     Had the same EXACT problem with a CP65 last month and posted it here. Same EXACT symptoms. I was told to check the bypass relays on the back. I took them off, reseated them, and the problem never came back.  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-10-2012 10:11 PM                       I assume you are talking about the film formats, 01, 04 05? First, what happens in bypass? Do you have a crackling noise? If so, which channel(s)? If no go to next step. Check the green lights on the 150 and then on the 242. If the center green light is on more or less in sync with Left and right channels, look next at the surround green LEDs. Is the surround LED on the 150 card on dialog, it's likely the 222 or 150 but could also be the center Cat. No. 64, or the output relays that was a topic recently. So, now you have a homework assignment.  |  IP: Logged Dominic Espinosa Phenomenal Film Handler Posts: 1172 From: Boulder Creek, CA. Registered: Jan 2004 posted 05-10-2012 10:16 PM                     Thanks, guys. I'll check it out!  |  IP: Logged Kenneth Wuepper Phenomenal Film Handler Posts: 1026 From: Saginaw, MI, USA Registered: Feb 2002 posted 05-11-2012 06:53 AM                     Sam, You are a great teacher and your help is always cheerfully offered. Thank you for all of your sharing here on the FORUM.  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-11-2012 12:23 PM                       Thank you Ken. You're not so bad yourself. I don't know about the cheerful part, that tends to vary depending, but I do try. I did this for Dolby Labs for 14 plus years and always enjoyed this part of the job. I also taught Dolby school for most of those years. Now, if only I could keep all that info from draining out of my skull.  |  IP: Logged Dominic Espinosa Phenomenal Film Handler Posts: 1172 From: Boulder Creek, CA. Registered: Jan 2004 posted 05-11-2012 06:58 PM                     Thanks for the guidance. So, I got down here to look at it and it's actually a Cp50 and I don't see a cat 222 card...  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 05-11-2012 08:21 PM                        Well, no relays. Center channel only "exists" after the 150 card, check the 150, swap a 64 and the output line amp is on the 111/117 card. Note: left and right output line amps are on the respective 22 cards. Louis  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-11-2012 08:53 PM                     Don't forget...the CAT 112 (switch card) also has the audio pass through it and if the Non-Sync/Opt switch is getting noisy...so can ANY of the channels.  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-11-2012 09:24 PM                       I have to correct Louis' statement. The Cat. No. 150 produces the center as well as the surround channel and if it is a version equipped with the green signal presence LEDs, you can "see' if it is decoding all 4 channels. Dominic, you should not ask for help until you know what you are dealing with. It's waste of time for all involved.  |  IP: Logged Tony Bandiera Jr Film God Posts: 3067 From: Moreland Idaho Registered: Apr 2004 posted 05-14-2012 01:00 PM                     Sam I agree but your statement to Dominic was a bit harsh. (Since you and I are currently dealing with the same irritation I understand it though. ) Dominic, if you find you need a CAT 150 or 117 card let me know, I haven't tossed the ones I listed yet...I might even have a CAT 112  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-14-2012 03:01 PM                       Tony, You are right, I do go thru bouts of cranky (bet you hadn't noticed) but you should get the model # close. 55 vs. 65 OK, easy mistake, but CP50 to anything else, no. It's my own version of tough love.  |  IP: Logged Tony Bandiera Jr Film God Posts: 3067 From: Moreland Idaho Registered: Apr 2004 posted 05-15-2012 02:27 PM                     LOL yep, and you're right about how the model confusion in this case is a big deal. Louis mentioned that the Left/Right line amps are in the cat 22 cards, is that correct? I didn't think so. I'm going to see our "friends" on the 23rd. Wish me luck.  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-15-2012 03:38 PM                       Louis is right about that part. It was some engineers idea of saving a buck and using a spare line amp on the Cat. No. 22's. This later got fixed on 517 upgrade of the 111/117 cards.  |  IP: Logged Dominic Espinosa Phenomenal Film Handler Posts: 1172 From: Boulder Creek, CA. Registered: Jan 2004 posted 05-16-2012 07:18 PM                     Thanks to you guys, so far. Sam/Tony/Louis I always appreciate your advice. Even if it comes with a scolding for being an airhead I tried the format card and had to wait a few days to see if it recurred. The center just fades in and out, as if you were fondling the gain. There's no crackling or distortion though.  |  IP: Logged

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