Film-Tech Forum ARCHIVE: CP65 + DA20 staying in DIGITAL after show ends?

This is topic CP65 + DA20 staying in DIGITAL after show ends? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Joe Redifer (Member # 3) on 05-18-2008, 01:34 AM:

Last week we had the new Helen Hunt megahit "Then She Found Me" in our large giant screen auditorium which features a Dolby Cat702 reader, DA20 and a CP65. Automation is the world famous Christie AM8 Basic. Every single time this show ended, the changeover would close, non-sync would NOT be selected, it would drop to SR really quick (because of the end cue) and jump back into digital. The film tails out silently and the projector/lamp/etc shut off normally, but the CP65 stays in Digital and does not drop out until Non-Sync is manually selected. This happened every single show... but only on that movie. When we moved Helen to another auditorium and put a different show in our large giant screen auditorium, the problem disappeared. The auditorium where Helen is living now has a CP650 with a BACP penthouse reader and it goes into non-sync just fine at the end of the show.

What could the culprit have been? Did Helent Hunt personally program some special code into the digital stream to freeze up my DA20? I am only at this theater a couple of days a week so I don't have a lot of time to troubleshoot, but I was about to swap out DA20s (we have one sitting around elsewhere for decoration).

Posted by Louis Bornwasser (Member # 3063) on 05-18-2008, 06:06 AM:

Joe; Is the system set up to go to Non Sync with a relay driven by changeover close? If so, is it good? I install such a relay on all automations for this very reason: it is "hard programmed." Louis

Posted by Joe Redifer (Member # 3) on 05-18-2008, 06:20 AM:

The changeover seems completely independent. However, if you press the STOP button on the automation, the changeover closes right away but the sound doesn't switch for 8 seconds, which lets the audience enjoy the film soundtrack ramping down. Very little thought whatsoever was put into its design. We got this automation at a garage sale, I think. Or maybe a thrift store, I forget.

Posted by Scott Norwood (Member # 30) on 05-18-2008, 10:31 AM:

Can the DA20 normally pulse the processor back into SR when the SRD track faults?

I could see something like this happening if the DA20 is set up for auto-digital (is yours?), but the connection from it to the processor's automation terminals is faulty and it can't pulse the processor out of format 10.

Posted by Sean McKinnon (Member # 612) on 05-18-2008, 10:33 AM:

I have seen this before on some prints with some automations. My theory on what is occuring may be wrong but the quick fix has worked every single time. I would try moving the position of your "show end" cue. It seems like it could be that the DA-20 switching the 65 into SR then back to digital could be occuring at the same time your automation is sending the "non-sync" pulse and it is getting "lost" or over ridden by the DA-20's pulses. This is most likely happening because there is good digital information after your cue for whatever reason, so when the DA-20 loses the digital info because of your cue it pulses the 65 into "SR" but then immediately picks up the good digital info after your cue and pulses back into "digital" at the exact same time your automation is trying to pulse into non-sync. What I would do is to try taking a peice of black leader, putting your cue on a few feet into it, and splicing it to the end of the print. This way the DA-20 should drop out of "digital" to "SR" and stay there until the automation pulses it into "non-sync" You just have to make sure that you give it enough time to drop into "SR" and stay there for a few seconds before you cue into "non-sync".

PS: This theory also explains why it doesnt happen with the CP-650. The CP-65 and DA-20 combo operates differently. The DA-20 is an independant peice of equipment that controls the CP-65 through command pulses just like an automation. The CP-650 has the digital decoder built in therefore it does not have use that method to control switching to and from digital. On the CP-650 your pulse into "non-sync" is being read because the 650 is not also receiving pulses from another peice of equipment.

Posted by Brad Miller (Member # 2) on 05-18-2008, 03:52 PM:

Joe, if you press STOP, the processor IS switched back to non-sync (regardless of how long it takes), right? If so the relay is fine.

Try putting a business card in the reader during a critical scene in a movie and see if it drops to SR. When you pull the card out, does it switch back to digital?

This will at least tell us if those two issues are working properly.

You should be using CA21s. I am outraged.

Posted by Joe Redifer (Member # 3) on 05-18-2008, 07:18 PM:

I think Sean might be the closest to being correct, however it still doesn't explain why the DA20/CP65 combo doesn't drop out of digital when there is no film in the reader after it tails out.

Brad, unfortunately the movie we are currently playing on our large giant screen (Bonneville) doesn't have a large enough audience or scenes important enough for me to do the business card trick. But when non-digital trailers run, it does revert to SR normally. When no film is running and I press Digital, it switches to SR before I even let go of the button.

Posted by Brad Miller (Member # 2) on 05-19-2008, 08:25 AM:

So to clarify, does pressing STOP make it switch to non-sync (sooner or later)?

Try moving the cue. That makes a huge difference in dts installs, but I've yet to see it cause a problem in SRD. There is a first for everything though.

Posted by Sean McKinnon (Member # 612) on 05-19-2008, 09:34 AM:

I have seen CP65's and DA20's stay in "Digital" before after the projector has stopped. I am not sure but I think it may have something to do with the motor relay being unlatched thereby causing it to stop looking for digital information or something?

Posted by Joe Redifer (Member # 3) on 05-19-2008, 05:54 PM:

I always get to the Non-sync button before the automation does, so I'll have to check on the STOP thing.