This is topic DTS Problem. Time code drop outs in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Mike Carro (Member # 232) on 02-05-2004, 12:15 AM:
I have a two drawer unit. It has been working fine until recently. The time code is not staying steady and drops out of digital. I tried tightening the tension but it doesn't do anything. I thought maybe it's the LED so , I have a spare reader and I put that in and... still the same problem. So, could it be a power supply issue? Any advice would be appreciated.
Posted by Adam Martin (Member # 641) on 02-05-2004, 12:26 AM:
Is this with different prints or a single print is doing this?
Posted by Mike Carro (Member # 232) on 02-05-2004, 12:45 AM:
Yes, different prints. It doesn't matter.
Posted by Aaron Sisemore (Member # 145) on 02-05-2004, 02:43 AM:
Do you have the latest ROM update installed [version 1.46]?
If you have a new enough reader, have you tried the reader LED calibration procedure ?
Has anyone tinkered with the lateral alignment screw on the reader (a definite no-no)?
All of these factors will affect timecode read performance.
If the LED calibration listed above doesn't fix the problem or you have one of the older readers without the LED voltage pot, you are likely going to have to get a reader on repair-exchange from DTS.
-Aaron
Posted by Michael Schaffer (Member # 1204) on 02-05-2004, 02:44 AM:
Next step: perform the reader LED calibration. The instructions are on the home page here under public additions.
Oh - Mr Sisemore was 1 minute quicker than me. Maybe then I could add that you may find that your reader does not have the trimpot. Then you are doomed - you have to send it in.
Posted by Mike Carro (Member # 232) on 02-05-2004, 08:55 AM:
I have older units. I don't think they have a trim pot. Where would it be located? And no, no one's tinkered withi it. they have a manufacture date of July '94. Could it be a problem with the CPU?
Okay and update;
My spare reader is newer than the other and it does have a pot. It was reading at 2v. I adjusted it. But it still does it. No quite as bad but it does drop out. Could the reader go out of allignment by itself? And is there a remedy?
If the green light on the reader goes on and off it means the reader isn't picking up the signal or does it mean the CPU can't read it?
[ 02-05-2004, 10:23 AM: Message edited by: Mike Carro ]
Posted by Mark Gulbrandsen (Member # 72) on 02-05-2004, 11:14 AM:
Ok, I beat both seismicmore and shlaffner by at least a minuite!
The pot is inside the time code reader. At the reader remove the T.C. cable with the power off! Then remove the four allen screws to expose the pcb inside. There might be a pot and there might not be one. I've seen em on older readers that have been modified or repaired in the past. No pot = A repair exchange for around 225.00 or so. You will get the new firmware 1.46 with the nre reader. be sure to install it if its not 1.46. You willalso get a bag of TCR mounting screws that includes the 70mm mounting stuff..... I suppose they have an excess of those to get rid of....
Anyway, if there is a pot them place your VOM probes on TP-1 and TP-2 and adjust the pot for 4 vdc with no film in the reader and no excess stray light hitting it either. Stray light does affect the reading. The reason for it going out of alignment is that the LED fades slowly over time. I find that if the DC setting is under 2.8 volts that things get pretty unstable. The green light is only an indication that TC is being read. Nothing to do with the CPU. You may also need to check your firmware which is located inside the unit. Foloow the DTS upgrade instructions on this site to see where to look for it.
Mark @ CLACO
Posted by Aaron Sisemore (Member # 145) on 02-05-2004, 01:04 PM:
July 1994? Those 'Jurassic-era' readers are likely goners by now especially if they saw constant use since then. By all means get new readers via repair/exchange, they will be freshly built ones with the adjustment pot in them.
Also if the firmware is a version HIGHER than 1.46, then 'downgrade' it to 1.46. The 'later' versions had some nasty bugs, and DTS actually went back to 1.46 and stayed there.
-Aaron
Posted by Mike Carro (Member # 232) on 02-05-2004, 01:08 PM:
Thanks everyone. I've contacted DTS and they're helping me out big time. Thanks for all your help.
Posted by Daryl C. W. O'Shea (Member # 1303) on 02-05-2004, 03:56 PM:
Having never seen the inside of an old reader. Is the only difference the addition of the trim pot (and possibly removal of a resistor), or is it an entirely different PCB?
Posted by Bruce Hansen (Member # 281) on 02-05-2004, 05:28 PM:
Check to make sure that the film is going into the reader, and comeing out of the reader, and into the projector without twisting, or pulling to one side or the other. Is there any flutter from the projector that could cause jitter in the timecode? If you have a scope, look at the timecode. If you can move the reader and DTS player to another projector, you may want to try it.
By the way, I know what the LED alignment instructions say, but the pot does not adjust the LED voltage, it adjusts the gain of the opamp. You can put a volt meter accross the feed to the LED (the red and black wires soldered to the board) and adjust the pot. The LED voltage will not change.
Something for anyone having problems getting enough gain out of the opamp: clean the LED, and the solar cell that is on the back side of the board that is in the reader (you have to remove the board to get to it), and clean the optical path inside the reader.
Posted by System Notices (Member # 2357) on 07-04-2005, 07:49 PM:
It has been 515 days since the last post.
Posted by Brian Hogan (Member # 940) on 07-04-2005, 07:49 PM:
i find myself in this same situation. our system plays fine for a few reels then it cuts out. ive been trying to trouble shoot and the problem is coming from the reader. ive been playing war of the worlds and the last 3 showings the reader cant read the time code for the last reel. it plays fine through the whole movie except for the last reel. im waiting on a multimeter so i can check the led voltage, but is it possible that it can happen? that possibly the whole print was clear enough for the reader to read, but then the last reel was maybe a bit tinted or something. just a bit darker so that a possibly week led could not transmit through?
ive had the same problem on mr & mrs smith. it would play fine for a bit then drop out. i dont know when exactly on that one, but i do on worlds. happens same spot everytime on it. any thoughts?
Posted by Mark Gulbrandsen (Member # 72) on 07-04-2005, 08:23 PM:
Besides bad print/disks the most comon problem is the 4 volt adjustment in ythe TC reader. Place your negative probe on TP-1 and the positive on TP-2 and the meter should be on the DC volts scale to read 4 volts. Adjust the pot in there to read 4 volts WITHOUT FILM THREADED on your meter. If your TC reader does not have this pot or yopu camnnot reach the 4 volt level then you will need to get an R/A TC reader from DTS. Also, has your player ever gotten any upgrade of any tupe?
Mark
Posted by Gordon McLeod (Member # 33) on 07-05-2005, 08:55 AM:
Bruce said "You can put a volt meter accross the feed to the LED (the red and black wires soldered to the board) and adjust the pot. The LED voltage will not change. "
True it adjusts the gain of the opamp that provides the TC output but also a Diode and Diode including a LED will have a fixed voltage drop across it if silicon based it is around .7volts and around .3 volts if germanium. That is why a resistor must be inserries with a LED to limit the current
Posted by Brian Hogan (Member # 940) on 07-05-2005, 08:17 PM:
good news: i was able to adjust the pot to get the reader to see the timecode! now my dts is rockin the house! ![[Big Grin]](biggrin.gif)
bad news: while trying to measure the voltage, my multimeter fell to the ground and now the meter wont move. ![[Frown]](frown.gif)
Posted by William Hooper (Member # 71) on 07-06-2005, 12:06 AM:
I don't want to seem too critical, since you seem to be a little inexperienced, but the correct way to drop a meter is so that it bounces once then falls 100 miles down an air shaft to never be seen again by a human being.
If you're just going to drop it in the booth, you're supposed to blow it up first on some high voltage & drop it while screaming technical language loud enough to be heard in the street.
Posted by Michael Wilkinson (Member # 2389) on 07-06-2005, 12:16 AM:
Okay, I have a 6-D unit with the 1.46 firmware and it is working fine. The only problem that I now have is with the DTS-ES processor no longer holds in ES...The unit has to be set manually otherwise it cuts in and out much like the 6D did prior to the 1.46 firmware install. (The ES proceesor is supposed to detect ES and Non ES prints and switch over automatically)
Any suggestions?
Posted by Mike B. Smith (Member # 2829) on 07-07-2005, 02:14 AM:
Intermittent playback on your ES could be a time code issue even though your DTS-6D is working correctly. If this system is utilizing the Time code to automatically switch into ES mode, check the cable, in this type of set up. A “Y” cable is connected from the DTS to the Time code reader head and the ES. It is always difficult to trouble shoot without the whole story, but has anyone changed the programming in the ES? Check to see if it is set up correctly to respond to time code input and all cable connections are good. Are you currently playing an ES feature or is this happening with all features? The easy way to tell if a DTS has ES since it is not always printed on the disc or the print is look at the serial number on the disc; feature serial numbers are normally four digits but an ES disc will have five, beginning with 65xxx. Currently the only show in ES I’m aware of is Star Wars.