Film-Tech Forum ARCHIVE: DTS Readers

This is topic DTS Readers - LED Power in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Paul Konen (Member # 41) on 06-23-2002, 11:45 PM:

Is it possible that the red led on DTS readers could get "tired" and start to have problems reading prints?

Can the power of the LED be adjusted like on the CAT-701?

I have a couple of readers that for some reels of a print, they read just fine, for other reels, they have trouble reading the timecode.

Thanks
Paul.

Posted by Brad Miller (Member # 2) on 06-24-2002, 12:47 AM:

We've got an original "Jurassic" reader at the Galaxy that is STILL chugging along fine. You have to have the lights off and no extraneous light to even see the green led on the reader, and trying to see the red led inside the reader is virtually impossible...yet it reads timecode fine and dandy.

I would bet your problem is the lateral alignment has drifted. Set it up with Karen to make a field adjustment, for there is a stiff penalty if you remove the "do not remove" sticker. (I forget what the penalty is, death or something like that. )

Posted by Paul G. Thompson (Member # 655) on 06-24-2002, 01:07 AM:

......and adjust it very carefully for the brightest steady green light. Before you do that, make sure the flanges are absolutely clean and free of wax and dirt build-up. Chances are, that is what happened to you.

Incidently, I think there is a little locking set screw to hold the adjustment in place. Don't reef on the adjustment screw without loosening the lock screw.

Posted by Manny Knowles (Member # 1171) on 06-24-2002, 02:46 AM:

Some DTS readers have a trimpot for the LED.

Unplug the D connector on the reader
Remove the cover to expose the D424 board
Plug the D connector in and turn on the DTS player to provide power to the reader

Use your meter and measure the voltage across TP1 and TP2. It should be 4 Volts. If the LED cannot get at least 3.5 V then DTS recommends doing an exchange/repair.

There is a DTS TechTalk bulletin that describes this procedure. If I can find the file Karen emailed to me I will forward it to you.

Posted by Antonio Marcheselli (Member # 373) on 06-24-2002, 04:49 AM:

Paul.

I recommend you to check the reader/projector alignment before touching the reader's lateral alignment. Try moving the reader, moving the auxiliary roller and add tension to the print. Also try Manny's procedure on the led tension.

If that does not improve your reliability, try the reader's lateral alignment.

Bye
Antonio

Posted by Darryl Spicer (Member # 711) on 06-24-2002, 09:28 AM:

Really the problem is two-fold. The reader can be weak and the timecode on some of the prints can have defects. We were having this problem on a couple of our projectors running Star Wars. We repaired exchanged the DTS readers but the reels stiill exhibited drops in timecode but not to the extent that the other readers were causing, that being dropouts to analog sound.

Posted by Karen Hultgren (Member # 395) on 06-24-2002, 11:48 AM:

Paul,

Yes, the LEDs can get "tired" and you need to test the voltage to the reader every year or so to be sure it is correct. I have a procedure on doing that, if is very easy, I'd be happy to email it to you. It is also posted on our online techcenter (look at dealer or service center notices).

If you'd like the procedure, please send me an email.

Karen at DTS
khultgren@dtsonline.com
www.dtsonline.com