Film-Tech Forum ARCHIVE: Proper Milliamp setting for Kelmar LED reader.

This is topic Proper Milliamp setting for Kelmar LED reader. in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Brad Allen (Member # 470) on 02-20-2008, 07:18 PM:

I have a Kelmar (sorry, not sure of part #) that was originally bought as a Infrared Reverse Scan Reader. I then purchased the visible light LED to upgrade it.

What is the proper Milliampere setting for this LED?
It use's the black Kelmar power supply.

Thanks!

Posted by Sam D. Chavez (Member # 1841) on 02-20-2008, 08:27 PM:

Brad,

I'll try to answer both your questions.

There is no ideal current on the LED. The lower the better as long as you can get it to Dolby level or in this case Kintek level.

Kintek uses the DC component the solar cell produces to simulate Dolby level so the general idea is to raise the LED current until you the cal is in range. All brands of Red readers were designed to be DC coupled to accommodate Kintek and of course they've been out of business for years.

Don't overlook the importance of getting the LED to give you peak level before turning up the LED current. Run a tone loop and move the LED bracket up and down to find the loudest signal.

This will get you started.

Posted by Brad Allen (Member # 470) on 02-21-2008, 03:03 PM:

Thanks Sam.
I'll redo all the LED alignment again.

Question, which way is the correct way for the Kelmar reader to be installed. It's not clear in the instructions. Meaning, should the wiring connections to the preamp be closest to the threading side of the sound head or not? Or does it matter?
Thanks.

Posted by Mark Gulbrandsen (Member # 72) on 02-21-2008, 04:09 PM:

Brad,
Set the cal. levels on the solor cell preamp to near maximum and then use the voltage adjust pot in the Kelmar power supply unit to lower the voltage back down to Cal level. Touch up the higher level channel to match the other channel then slightly tweek the power supply up or down again as necessary so both are at the cal. level. This will place the LED at the lowest possible operating current for your particuluar system and greatly extend the life of the LED.

Mark

Posted by Louis Bornwasser (Member # 3063) on 02-21-2008, 05:13 PM:

The wiring terminal should be toward you and the open door. I don't think it will fit the other way. If it did you could simply reverse left for right; in this system it does not matter since it is a "mono with surrounds" system.

(Plenty of Dolby Digital systems on E-bay.) Louis

Posted by Brad Allen (Member # 470) on 02-21-2008, 07:16 PM:

Thanks.

Mark, I'll give that a whirl.

Louis, fyi both of these were purchased from you several years ago. I'm pretty sure that when the lense of the reader was installed, it was attempted to install it with the wiring terminal on the door side, and the door hit it when closed, so it was turned around the other way purly for phyiscal fit reasons, since it sure is not obvious, which end is up. [Big Grin]

As far as proper A chain alignment goes, does it "matter" which way it is installed.

Thanks, the help is appreciated. [thumbsup]

Posted by Louis Bornwasser (Member # 3063) on 02-21-2008, 09:07 PM:

If you rotate it, reverse the l & r so that the channels make sense. I seem to recall this has stereo surrounds with "bleed" from left & right, so it does matter. Louis

Posted by Steve Guttag (Member # 268) on 02-21-2008, 10:23 PM:

Brad, report back with your results...I'm interested to see if you get the CAL LED to light up.

Posted by Brad Allen (Member # 470) on 02-22-2008, 05:06 PM:

Will do. Thanks everyone!

Posted by Jeremy Weigel (Member # 4208) on 02-22-2008, 08:35 PM:

For what its worth I was able to get CAL/BAL on our Kintek 2010's and 700 with the BACP LEDs and still had the static sound in the audio (refering to the other thread).

Posted by Louis Bornwasser (Member # 3063) on 02-23-2008, 07:05 AM:

There is a "fully loaded" CP-65 on Ebay right now. The Kintek is garbage (film done wrong.) Louis