I have a customer who has a TSU7500. There is an IR sensor mounted under the plasma TV in the living room leading to all of the IR emitters connected to A/V equipment housed in a cabinet in the next room.

PROBLEM: The TSU7500 correctly controls the cable box (Charter Cable) when you point it directly at the cable box. However, it does NOT control it when you point the TSU7500 at the IR sensor located under the TV. Ironically, when you use the original remote that came with the cable box, it DOES control the cable box when pointing it at either the IR sensor or directly at the cable box. And interestingly, the TSU7500 correctly controls the other components (Harman Kardon A/V receiver and Samsung DVD player) when pointing at the IR sensor.

QUESTION: So why would the Pronto not be able to control the cable box when pointing it at the IR sensor, and yet the other components have no problem responding consistently through the IR sensor? (NOTE: Sometimes the cable box responds and sometimes it doesn't when going through the IR sensor, yet the cable box consistently responds successfully when pointing the TSU7500 directly at it.)

I was thinking that maybe the problem could be the IR sensor/emitter, but then I ruled that out after I found that the original remote for the cable box works just fine when using it through the IR sensor.

Thanks for any advice you can share for this problem.

Could the Pronto be sending out the code to the IR receiver and the cable box at the same time? If the box is near by and not totally hidden this could cause a problem.

The Pronto has a wide array (3 eyes) oppossed to the OEM remotes (1 eye).

This has caused me much grief...

That's a very good point, Roddy. Thanks for pointing that out about the wide IR dispersion.

However, I seem to recall the problem still happening even with the wooden cabinet door closed. But, I'll have the customer test that for me (i.e., with the door closed) just to be sure. (Once I hear back from the customer on the outcome of the test, I'll post an update of the results.)

Assuming that doesn't resolve the issue, anyone else have suggestions on what the problem could be?

Different remotes xmit with different IR strengths. The cable remote may be stronger than the NG remote. Who knows??

With the Plasma off, try controlling the equipment with the 7500. If this works, then replace the IR sensor with another that is more Plasma/Flourescent Light friendly.

The last option, that I don't recommend is to replace the 7500. I don't recommend this because I'd be lost without my 7000.

Without realising it I posted prety well the same question. I did however notice that the original Foxtel remote had the same effect on two occasions. Hope we get some answers. Regards Troy

Google "IR interference plasma". You will find lots of references that discuss the plasma IR interference problem, which may be the source of your difficulty. I had a client with this problem. He solved it by situating an IR extender receiver in a location not subject to the interference and running emitters to the equipment that was affected.

Thanks for all the info guys! I'm still waiting to get a call back from the customer to find out when they'll be available for me to test these things. Once I'm able to do that, I'll post the outcome.

IR can be a nightmare on some cable boxes like Scientifics. The best solution to you IR flooding problem is Audioplex IRBug-PL Adjustable. They are available as a plug-in emitter or hard wired emitter, just turn the signal strength down to half and they work like a champ. Also try using Audioplex plasma proof IR receivers (expensive, but they work great). You can get regular receivers to work with plasmas, believe it or not they work when placed on the back down low facing the wall.

Some cable boxes operate at frequencies that some eyes don't pass. Russound makes a part called a 56k remodulator that cures many problems with some cable boxes. I can't remember the specifics of the part but you can check it out on Russound's site. I think it is like $15 or $20, much cheaper than an Audioplex eye.

Well, I was finally about to get back out to the customer's house about a week ago to test things. As it turns out, having the plasma TV turned off did NOT make any difference (i.e., the cable box still did not respond consistently with the plasma turned off). I did discover there is a "sweet spot" whereby if you point the Pronto at the IR sensor at just the right angle when you're sitting at a particular spot in the room (e.g., turning it 45 degrees to the right), the cable box does seem to respond consistently. It's just really odd that the other components (i.e., DVD player, A/V receiver) respond fine regardless of where you're sitting and pointing the remote.

Thanks guys for the suggestions on the Audioplex eye and the Russound remodulator. For now, the client is content with things now that they know about this "sweet spot" where they need to point the remote. But, if things really start acting up again, I'll probably contact the customer's installer to have them put the Russound remodulator in place to see if that does the trick.

Thanks again to everyone for their advice in helping me troubleshoot this problem. It is greatly appreciated.

i really wouldn;t recommend ir systems for plasmas. the new RF systems are designed for the plasma's and don't fail on you.