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Author Topic: My Dolby CP500 Died! Manny Knowles "What are these things and WHY are they BLUE???" Posts: 4247 From: Bloomington, IN, USA Registered: Feb 2002 posted 07-20-2003 03:55 PM                     This is at a remote location so I haven't seen the unit yet since the failure occurred. First, the SRD tracking went south but as I mentioned in another thread this 701 unit has been three years with the same LED so I figured that was the source of that problem. Now, the analog sound has developed problems. According to the manager it was "cutting in and out" presumably going mute since there was no SRD. Also, that is a new LED in the analog head with a relatively fresh A-Chain alignment (done in April). The manager then called about a day or so later to report that the analog sound had died completely. He mentioned that "the screen [on the processor] went all screwy for a while." I instructed him to run in bypass mode and they are testing it all day today. I will hear from that location either tonight or tomorrow as to whether their testing went smoothly. I will probably get to this theatre on Tuesday. The analog and digital have two things in common -- the processor and the power source (in the building) so those are my main suspects at the moment. In any event, something seems to be the matter with the processor and it MAY be tied into a problem with the power. As this is the only CP500 in our chain I can't do any swapping of boards or anything like that. So I'm wondering how exactly to troubleshoot this situation without having to send the processor away for repair. (Seems to be where this is headed.) What are your thoughts on this? Do you need more information?  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-20-2003 04:28 PM                     Most likely powersupply related Check the molex connector on the powersupply as I have had them fry also the regulator board may have failed  |  IP: Logged Manny Knowles "What are these things and WHY are they BLUE???" Posts: 4247 From: Bloomington, IN, USA Registered: Feb 2002 posted 07-20-2003 06:08 PM                     Actually, now that you mention that...I've had the analog LED power supply fail before, too and the symptom is indeed the same -- analog cuts in and out before dying completely. However, if they are able to get reliable analog sound in bypass mode then I'd be inclined to look to the processor.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-20-2003 07:15 PM                     I was refering to the powersupply of the CP500  |  IP: Logged Manny Knowles "What are these things and WHY are they BLUE???" Posts: 4247 From: Bloomington, IN, USA Registered: Feb 2002 posted 07-23-2003 04:24 PM                     Okay, I went, I saw, I conquered...Here's what I found... Analog sound was well behaved. I could not find anything wrong but that doesn't mean the problem doesn't exist. Come-and-go problems have a nasty way of hiding whenever I'm in the building. As for the digital side of things... LED needed replacement. The intensity pot was turned all the way up and the reading was something like 1V. A new LED solved that and we went from getting straight F's to getting a solid 7. The CCD needed alignment of all kinds. I was able to improve focus, azimuth and lateral settings but the error rate did not improve all that much. The best I could get was a 6. Then I switched out from my 69T loop and made a loop from a trailer. The rate improved again...to a 4. Test screened a movie and we got 2's, 3's and 4's. No dropout to analog at all. There is no bypass power connected to this particular unit so when they "ran in bypass" they were using a softkey.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 07-26-2003 11:50 AM                     Actually the Molex connectors burning up have been a problem in just about every Dolby (digital) product ever made!! I just repaired two Cat 700's that had burnt up Molex connectors in them last week. The thing thats interesting in the 700's is the fact that there are three pads on the pcb for the plus and minus connections but only two are used. Here the plus and minus could have each had an extra connection made there and possibly allieviated the problem completely. I've found and repaired burnt up MOLEX connectors in these Dolby products numerous times.....DA-20's, CP-500's, CAT 700's CAT 701's. In each case I get rid of the connector completely and slder the wores to the PCB. I've never been back to repair one that has been de-molexed!! I really wonder how many entire power spply PCB's have been replaced in units over the years that didn't really need to be?????? The clue with present day Dolby equipment is...always check the MOLEX's carefully before assuming a dead unit has other problems!! Mark @ CLACO  |  IP: Logged Manny Knowles "What are these things and WHY are they BLUE???" Posts: 4247 From: Bloomington, IN, USA Registered: Feb 2002 posted 07-26-2003 04:12 PM                     So does MOLEX just generally suck or does Dolby use it poorly?  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-26-2003 07:58 PM                     If improperly assembled and crimped Molex connectors suck If properly done they are great  |  IP: Logged John Walsh Film God Posts: 2490 From: Connecticut, USA, Earth, Milky Way Registered: Oct 1999 posted 07-27-2003 12:07 AM                     Agree with Gordon... the only thing I will add is often a company will not buy the correct dies to properly crimp the terminals. They will try to use dies they already own in an effort to save money. I doubt Dolby did this since they usually try to do everything right, but I must admit I have also had several problems with their Molex connectors.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 08-01-2003 09:10 PM                     The thng about the Molex's in Dolby's equipment and others that fail is that usually its NOT the crimp part that is done wrong..... What I see is that the male pins are so crappy that the quality of connection is sometimes just lousy. Also, Dolby has screwed up bu using female pins with too low of current handling. Mark  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 08-01-2003 11:25 PM                     Yep, there are various grades of platings and actual socket construction. Most just use the simple leaf socket...those are the ones that are most prone to fail under high-current. You have a single side of a square pin with a tin-plate doing all of the conducting. Molex also has 3-sided sockets that do a much better job of using the material at hand. They would be a better choice in these high-current applications. I have also found that the male pins are often not soldered to the PCB as well as they ought to be (not just Dolby)...it's like wave solder machines just don't like to take to Molex pins! Steve  |  IP: Logged Manny Knowles "What are these things and WHY are they BLUE???" Posts: 4247 From: Bloomington, IN, USA Registered: Feb 2002 posted 09-29-2003 11:51 PM                     A few days ago I had to do another SRD head alignment and it seemed the best I was going to get was a 5 for the error rate. I couldn't understand it because this was a new 69T loop I was using just for this alignment. Finally, I gave up and made another loop out of an old -- used -- trailer and got a 2 with the same settings. This isn't the first time that I've seen this. I resurrected this old thread because I noticed it back when I did this job too...but that was a used 69T loop I had been using and so I just assumed "wear and tear." How come my Dolby test films have such high error rates? I've resorted to using trailers for aligning the SRD heads now. One would have thought that Dolby's test films would be PERFECT. What gives? Why are trailers so much better? Does everybody else get high errors using the Dolby films too? Or did I get hold of a bad batch?  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 09-30-2003 12:34 AM                     ALL of Dolby's loop are crap like that Manny. What I do is load up a bunch of trailers on a reel and run them through. I make a note of the settings via DRAS as each one plays, then sit down and figure out which of the trailers is the most "average" of all the settings, and use that as my master source of loops. Dolby will sell you a piece of calibrated film at a ridiculous price tag, but my method has been steadily producing 0-3s on every reader I have. That's good enough for me.  |  IP: Logged Jon Bartow Master Film Handler Posts: 287 From: Massachusetts Registered: Nov 1999 posted 09-30-2003 07:37 AM                     What I have been doing is using an OLD loop of 69P (mostly because that happens to be the last loop in the projector after an a-chain) to align the Dolby Digital readers. I know that if I can get the reader/processor to stay in digital reading a 5-5. than it's aligned correctly. (and will often play a 3 or lower with a new print). If I am just doing a DD alignment then I have a 10 minute reel of trailers that I know are decent to play with. Jonathan  |  IP: Logged Manny Knowles "What are these things and WHY are they BLUE???" Posts: 4247 From: Bloomington, IN, USA Registered: Feb 2002 posted 10-21-2003 05:56 PM                     In case anyone is interested the calibrated test film to which Brad referred is Cat. 530 and it is essentially a section of Cat. 69T that has been marked up to help align the DD readers with DRAS.  |  IP: Logged

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