Film-Tech Forum ARCHIVE: Christie AW3 Problem

This is topic Christie AW3 Problem in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by William Dickson (Member # 314) on 01-06-2003, 04:18 PM:

Yesterday I got a call from a projectionist that said when he was threading a film the return platter would spin for a couple seconds, stop, then start again. I went in to check it out and found the plug for the LED assembley was loose. After I reconnected it, I checked the LED intensity and got no reading. When I put the platter card back in, the platter spun just fine. I took the card out and once again could not get a reading on my meter. What could cause this? I checked all the obvious things: meter operational, platters turned on after I removed the cards and hooked up the meter, feed arm set to full speed, etc. Any ideas? Thanks in advance.

Posted by Paul G. Thompson (Member # 655) on 01-06-2003, 06:45 PM:

Did you get any reading at all with the card in and out? Remember...it is a DC voltage. Is it possible you were on the wrong function with your meter?

Posted by William Dickson (Member # 314) on 01-06-2003, 08:09 PM:

What I was measuring was the the resistance in ohms to set the LED intensity. There was DC voltage with the card in as the motor was running.

Posted by Matthew Bailey (Member # 601) on 01-06-2003, 08:58 PM:

Don't take voltage reading with your meter in ohms setting.
It can damage your meter.

Posted by Tim Reed (Member # 137) on 01-06-2003, 09:58 PM:

Pins 14 and 16 are across the LDR assembly. That is a pure resistance, you don't read it with a voltmeter.

Posted by Bob Koch (Member # 1062) on 01-06-2003, 10:05 PM:

Post deleted by moderator. Please read the FAQ before posting again.

Posted by Jon Bartow (Member # 241) on 01-06-2003, 10:20 PM:

Actually it's pins 12 & 14. They are the two pins farthest from the platter decks in each of the motor speed card slots.

Double check that the meter is set for Ohms (or the greek omega symbol) not voltage or diode funtion etc. Are you removing only the speed card for the deck in question or are you removing the LED intensity card as well? Can you use your equipment to check another deck? Are any of the selector switches pushed in? Do any of the cards or the transformer or motor resistors show signs of damage?

It sounds to me like there is a loose connection somewhere or a burnt trace on a card (possibly the LED intensity card or on the back of the selector switches. It is also possible that the motor needs servicing (i.e. new brushes or a good cleaning)

PS. Mr. Koch: you need to read the FAQ's. in particular the last paragraph [Frown]

Posted by Manuel Francisco Valencia (Member # 710) on 01-06-2003, 10:52 PM:

Check the filter to make sure it rotates smoothly. Also check the spring as well.

Posted by Tim Reed (Member # 137) on 01-07-2003, 01:49 AM:

quote:
Actually it's pins 12 & 14.

Sorry about that, thanks, Jon. I'm a little out of practice... always seem to be 2 off on everything... [Confused]

Posted by William Dickson (Member # 314) on 01-07-2003, 12:14 PM:

I guess my big concern is how can a platter appear to run properly when I am getting no reading at pins 14 and 16 on that card slot? Yes the meter is working properly, set properly, and the platter is not selected for build up.