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Topic: The little projector that couldn't

Bryan Redemske
Film Handler

Posts: 70
From: Cedar Falls, IA, USA
Registered: Feb 2000

posted 04-17-2000 10:10 AM

Here's our problem here in sunny Waterloo, IA - We have a projector that, for the most part, runs well, takes care of prints and does its job. However, every so often (randomly), it'll just stop and the alarm will go off.

There is no reason for the stoppage. When you hear the alarm, you suspect that maybe it's wrapped, or there are little monkeys using it as a playground...but nothing.

I'm not at the theatre right now so I don't have all of this stuff written down, but it's on a Speco platter, it's a Century head and it is Dolby Digital equipped. The failsafe is a component engineering one with all of the little lights on it. Sorry, no model numbers. Yes, it's clean.

My question is, do we have a short in there somewhere? Some bad wiring perhaps? Is there a reason this projector decides to just stop and beep at us?

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Ken Layton
Phenomenal Film Handler

Posts: 1452
From: Olympia, Wash. USA
Registered: Sep 1999

posted 04-17-2000 10:27 AM

Sounds like you have the old model Component Engineering failsafes. Look at the little circuit board above the big black exit roller on it. Is there a red dot anywhere on the led assembly? No red dot means old and should be upgraded to the newer assembly.
Red Dot means new style.

What brand/model is your automation?

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-17-2000 10:29 AM

Bryan:

Sounds like the failsafe is sensing that the film has run out, or broke, when it didn't. I'm sure others using the Component Engineering failsafe (or Bill Purdy himself! ) have suggestions to diagnose and fix your unit's problem. First thing I'd check was the tension and alignment of the film through the failsafe.

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com

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Bryan Redemske
Film Handler

Posts: 70
From: Cedar Falls, IA, USA
Registered: Feb 2000

posted 04-17-2000 10:33 AM

Ken,

not being at the theatre, (actually, there's a bunch of 4th graders running around - i'm a teacher, too) i couldn't tell you exactly. I'm thinking Xetron...it's a great big thing...console projector? i'm sorry i sound like a total newby...basically the lamphouse and automation are all in the same place. our other ones aren't like that.

yes, it does have a red dot. what i've noticed, though, is that you can have the film threaded through, but not in the proper path...as in around the rollers but not in the groove...it still reads okay for film presence...

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Tim Reed
Better Projection Pays

Posts: 5246
From: Northampton, PA
Registered: Sep 1999

posted 04-17-2000 07:32 PM

Check the take-up trolley on the platter. Make sure the carriage travels up and down absolutely smooth, with no catches or binds. A rough excursion could cause a momentary "hiccup" in the film between the exit roller on the projector and the platter takeup.

It might be a long-shot, but I've seen it happen before. Good luck!

------------------
Better Projection Pays!

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Bill Purdy
Expert Film Handler

Posts: 139
From: Seattle, WA
Registered: Oct 1999

posted 04-18-2000 09:45 AM

Bryan,
Ken Layton is correct about the presence sensor upgrade. The only trouble is that there actually have been two upgrades and the assembly people just kept putting the same red dot on them. We probably should have gone to two red dots or some such. At any rate, look at the underside of that sensor assembly and see if there is an IC chip on it. It will be an 8 pin chip. This is the latest version. The other thing to look for is the contour of the large black roller. Look at the grooves under the perforation area and see if they are "Vee" shaped. Also, and more importantly for your problem, look at the relieved part of the roller just into the picture area. This is where the presence is sensed and there should be an angled surface on the roller. If you stick your head around front of the projector and look back you can see that there are four little sensor units hanging down. The outer pair are for motion sensing as they are looking at the perforations. The inner pair are the presence sensors which just look at the film. (This is why you can sometimes see presence even if the film is not seated fully in the roller.) It is below the presence sensors that there need to be angled surfaces. When estar based film came along we had to increase the sensitivity of the sensors and then we found that we were reading the rollers and so we then angled the surface of the roller so that less light was bounced back. While you are looking back at the unit, make sure that the assembly is parallel to the axis of the roller. These sometimes get hit and bent down a bit.

I gather from your original question that your stoppages are totally random. If there is any pattern, such as always at the same place in the reel, there are other things to think about.

Let me know if there is anything we can do to help you. We do not approve of either black screens or white screens.

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Randy Stankey
Film God

Posts: 6539
From: Erie, Pennsylvania
Registered: Jun 99

posted 04-18-2000 02:32 PM

Have you checked all your rollers going from the bottom of the proj. / failsafe, all the way back to the platter?

We had a lot of trouble with failing failsafes. We changed the sensor heads and there was STILL one that dropped out.

We found that the lower magazine roller under the proj. was the fault. The keeper was too tight and when a splice would go through it would catch. The momentary jump in the film would cause the droppage.

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Jason Burroughs
Jedi Master Film Handler

Posts: 654
From: Allen, TX
Registered: Jun 99

posted 04-18-2000 06:35 PM

Is this projector interlocked with any other projectors? If so have you noticed if the projector in question stops when annother film drops?

I've seen a few instances that due to bad wiring an automation will pick up the signal from annother projector on the same interlock circut and stop it as well. Also is your location known for any type of power surges, spikes or dips? It would only take a momentary lapse in power for the relays to close or open and signal a "film break".

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John Eickhof
Jedi Master Film Handler

Posts: 588
From: Wendell, ID USA
Registered: Jan 2000

posted 04-18-2000 11:11 PM

If it is a Xetron automation (MAXI...)
Check for faulty 120V NEUTRAL on the circuit that supplies power to the automation. The older maxi's are less sensitive to vltage problems, however, the models of 7-8 years ago are very sensitive to transients, or any
low voltage or 'brown out' situation.
(This applies for christie AM-5,7,8, and
Kelmar seies IV)

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Chad Souder
Jedi Master Film Handler

Posts: 962
From: Waterloo, IA, USA
Registered: Feb 2000

posted 04-19-2000 09:58 PM

I thought I'd give Bryan a little help. Its a component engineering automation mounted in a kneisley console with century heads, reverse scan led optics, and an older (10 yrs?) speco platter system. The problem is pretty infrequent. Maybe once every couple weeks or so.

------------------
"Asleep at the switch? I wasn't asleep, I was drunk!" - Homer Simpson

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99

posted 04-20-2000 02:20 AM

With that setup, I think Tim Reed has the best guess. Make damn sure that platter takeup elevator roller travels freely. Get yourself some projector oil on a cloth and wipe the two rods down and move the elevator roller up and down to distribute the oil. Some people say use WD-40 on this, but I find projector oil works best. I'm sure there are differing opinions on this, but working with SPECO platters and CE failsafes in the past, I can almost guarantee you that's your problem.

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Bryan Redemske
Film Handler

Posts: 70
From: Cedar Falls, IA, USA
Registered: Feb 2000

posted 04-20-2000 10:03 AM

thanks chad. i checked the takeup elevator and it's clean now. there were a couple of rough spots (dirt and other assorted sticky things) that should be gone now. i didn't put any oil on it or anything, but it's clean. now we just wait....thanks for your help everyone!

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

posted 04-20-2000 10:18 AM

There is a product called Slipicon dry silicon spray that I have had good luck using

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