Film-Tech Forum ARCHIVE: Dolby CP650 Analog Digital Switching?

This is topic Dolby CP650 Analog Digital Switching? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Andrew Bangs (Member # 4938) on 10-04-2008, 12:06 AM:

Is their a way to disable the auto switching of digital to analog when faults are present with this unit?

Posted by Joe Redifer (Member # 3) on 10-04-2008, 12:43 AM:

Yes, realign your reader and/or get a new LED for it. If it can't get enough good digital data, it simply HAS to revert to analog. What you are hearing is probably what I call "F-ing" where it doesn't quite drop out but you can still hear it clicking and sometimes chirping. Make sure the reader is threaded correctly with the proper tension.

Posted by Demetris Thoupis (Member # 833) on 10-04-2008, 02:22 AM:

Andrew isn't there a tech you can call in for a day or 2 to do complete A-Chain on all your readers? You seem to be having a lot of issues with the Horizon equipment.
Demetris

Posted by Monte L Fullmer (Member # 2797) on 10-04-2008, 03:12 AM:

One could disable the "target" assignment for FORMAT 10 so the automatic switchover is disabled when the reader senses the track on the film.

..or, just turn off the LED power supply that feeds the Digital Reader..or, simply unplug the green phoenix harness from behind the reader. Or, put a piece of black tape in front of the Digital camera. These steps are sure-alls of prevent Dolby Digital from engaging.

Posted by Marin Zorica (Member # 1716) on 10-04-2008, 05:40 AM:

Or just use FORMAT 05 :-)

Posted by Marco Giustini (Member # 4544) on 10-04-2008, 07:46 AM:

As told, the unit MUST drop to analog if some error is read, otherwise silence will be played.

But if you mean to disable analog switching for test purpose, you can enter the install menu and on the "reversion mode" (if memory serves) set "no reversion" instead of "normal".

This way you will heard all digital garble too when SRD cannot be properly decoded.

If you just want to know when the unit reverts, just turn off the analog LED.

If you're referring to some trouble you have with your unit because it reverts too often, an A-Chain is what you're serarching for [Smile]

Marco

Posted by Andrew Bangs (Member # 4938) on 10-04-2008, 12:51 PM:

Thank you All I think I have the answer and yes tis is just for testing purposes I need to hear the Digital so I can tell my Boss what the problem is But any time it gets bad I it reverts on me. Yes right now these horizons are being a pain but right now I think it might be due to bad maintenance over the years. I just took over a couple months ago and I have been fixing so many things that now it is time for the sound. also I just found this uber-wonderful resource and frankly as you can tell I can't get enough. We are making plans for a tech to come out but a we are in the middle of nowhere and the tech we get has his own theatre it will take some time before he can make it. Which means I just have to keep putting out fires and applying band-aids. but The more I know before he gets here the better prepared I can be for when he does get here and when he asks what's the problem my answer won't be "this projector" or "the sound"

Posted by Monte L Fullmer (Member # 2797) on 10-04-2008, 09:15 PM:

Ouch .. classic case of "Damn the Lawyers! Guilty until proven innocent!"- you inherit problems that wasn't yours, but get the rip-on if you didn't fix it.