Film-Tech Forum ARCHIVE: Help with Hearing Assisted Devices

This is topic Help with Hearing Assisted Devices in forum Ground Level at Film-Tech Forum ARCHIVE.

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Posted by Martin McCaffery (Member # 37) on 06-17-2014, 10:45 AM:

UltraPhonic IRC 20.

We had to move the emitter when we went to digital. Disconnected it from the CP650 H/I Output port. Now that it is plugged back in, all we get is static from the headphones even when standing in front of the emitter.

Any suggestions on troubleshooting so we can get this back? Seems like a work or it doesn't situation.

Posted by Louis Bornwasser (Member # 3063) on 06-17-2014, 06:31 PM:

Are any LEDs lit, I mean the single red one (power). Start there.

You mean the DIGITAL tech didn't know how to fix this? Worthless? Yes most won't work on dimmers and HI systems.

Posted by Martin McCaffery (Member # 37) on 06-17-2014, 08:23 PM:

I will check them when I can. We just didn't get around to working on them at the time as they were working, as far as I know, when we started.

Posted by Harold Hallikainen (Member # 5405) on 06-17-2014, 10:38 PM:

The IRC-20 is before my time (I designed the IRC-28(C)), but USL supports almost every product ever built. Give us a call!

It sounds like the carrier is not coming up. The IRC-20 detects the presence of audio, then brings up the 95kHz carrier. It is kept up for about 30 minutes after the last audio detection. If the IR panel is still connected to the HI output of the processor (CP-650, if I recall correctly), all should continue to work. See if the audio presence LED on the back of the IRC-20 flickers with audio present. If not, try turning up the sensitivity control on the IRC-20. Try hanging a pair of headphones across the audio line going from the processor to the IRC-20 to make sure there is indeed audio there.

And, if all else fails, give us a call!

Harold
Engineering, USL

Posted by Dave Macaulay (Member # 813) on 06-18-2014, 01:05 AM:

The panel sensitivity adjustment may have just been accidentally turned down during the move?
If the panel has a power red LED that's on, then it has power at least. As I recall, the signal LEDs don't come on without an audio signal - you can "see" these IR LEDs by pointing a digital camera at the panel - cell phone or whatever - with the IR LEDs on, the panel lights up brightly in a digital pic or camera display.
I doubt if the CP650 would suddenly cease to pass HI audio, but you can check with headphones or whatever. If there's signal on the cable going to the panel you need to check that it actually gets there.

Posted by Ken Lackner (Member # 1002) on 06-18-2014, 03:18 PM:

quote: Louis Bornwasser
You mean the DIGITAL tech didn't know how to fix this? Worthless? Yes most won't work on dimmers and HI systems.

Excuse me? I've kept my mouth shut for a long time, but I find statements like this quite offensive. Others, who shall remain nameless, have said stuff like this over the years, too. STOP. There are plenty of qualified and talented technicians out there who know how to work on 35mm and digital and audio and any other equipment in the booth. Yes, some installation organizations just hired warm bodies to do full-complex conversions as quickly and cheaply as possible, and I've encountered the results of that type of work. But please don't assume that anyone who installs a digital projector doesn't know what he or she is doing. Furthermore, statements like that are unnecessary and contribute nothing to the topic at hand. [Mad]

</rant>

Posted by Louis Bornwasser (Member # 3063) on 06-18-2014, 06:59 PM:

I tried to retire, but I still have to fix dimmers and hearing systems. Louisville area digital installers WILL NOT touch anything they did not sell or install including power amplifiers and speakers.

Posted by Martin McCaffery (Member # 37) on 06-18-2014, 08:39 PM:

Well, in our case we didn't ask the tech to check.

Where it stands now, I've talked to USL. We have the green power LED and the red sound LED, though the red does not flicker as it is supposed to. Playing with the input volume doesn't do anything. Next step is to get a set of headphones I can plug into the H/I and see if I get something other than static. It will be a few days before I can do that.

Posted by Manny Knowles (Member # 1171) on 06-19-2014, 12:25 PM:

Sounds like maybe Louisville has issues. I see no reason to paint an entire segment of the industry with the same brush.

Posted by Ken Lackner (Member # 1002) on 06-19-2014, 12:41 PM:

What Manny said times infinity.