Film-Tech Forum ARCHIVE: USL BACP DTSR reader noise

This is topic USL BACP DTSR reader noise in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Jeff Else (Member # 4063) on 12-19-2006, 03:30 PM:

we are running USL BACP DTSR-20 (or is it DSTR-20) dolby digital readers in all three of our theatres, and they make a loud sort-of film rattle noise, that is audible in the auditoriums. it seems to be coming from the sprokets on the sproket wheel, and if I pinch the arms that hold the film secure on the sproket roller the noise stops, although this seems to sort-of unseat the film properly. what can I do to adjust and get rid of this noise?

Posted by Sam D. Chavez (Member # 1841) on 12-19-2006, 11:19 PM:

Are the readers decoding the SR.D track? What is the the error rate? Does pinching the rollers reduce the error rate?

I have a couple of ideas but I would like more information.

Posted by Monte L Fullmer (Member # 2797) on 12-20-2006, 12:36 AM:

interesting, for I have some CAT-701's doing basically the same thing..sprocket run noise coming from the center sprocket - but not as loud.

I checked for hooking teeth, but didn't notice any for I thought about reversing the sprocket to see if this clears up, but it only happens on certain prints, not all prints..

Posted by Phil Ranucci (Member # 3820) on 12-20-2006, 01:07 AM:

I've noticed a 'whizzing' noise on our 701 and BACP readers and found that they were being threaded with too much tension. Don't believe it was loud enough to hear in the auditorium, but then again I didn't go into the house and fixed it in the booth.

Posted by Frank Dubrois (Member # 3042) on 12-20-2006, 03:13 PM:

Ours didn't make noise, but the error kept dropping to F. By pinching the rollers together, we were able to get the error rate back to a solid 3-4. Is there a more permanent fix? They arent that old to be going back to soon.

Posted by Jeff Else (Member # 4063) on 12-21-2006, 01:12 PM:

yes it is the SRD track. the error rate is fine, well, I should say is about 3-4 on two of the projectors, and about 5-6 on the third, but it stays the same when the rollers are pinched, and it even appears that the film sort of pops half off the sproket roller when I pinch (although it still runs) I believe the tension is correct, although perhaps I'll experiment, but, anyway they all make the same noise on just about all prints, although sometimes not for like the first minute of play or not for the last. So....

Posted by Monte L Fullmer (Member # 2797) on 12-21-2006, 03:11 PM:

quote: Frank Dubrois
By pinching the rollers together, we were able to get the error rate back to a solid 3-4. Is there a more permanent fix?

...you think that you have a drag problem with the scanner drum on why you need to pinch the rollers together to get rid of the "FAIL" reading? Or, the airpot dampners behind the arms aren't doing their thing too well, rollers are all grooved out from running together, or you need a bad case of a tuneup on that one reader.

..some areas to look at.. - Monte