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USB-UIRT too sensitive

Posted:
Sun Jan 09, 2005 10:39 am
by borgs
Hi,
I'm having trouble with my USB-UIRT. In dark conditions it works perfectly, unfortunately it is unusable whenever there are any lights on in the room.
I realise that energy saving light bulbs give out some infra-red but none of my other devices IR receiver LEDs blink when the lights are on.
Could you please tell me how I reduce the sensitivity of the device as I do not want to replace my light bulbs with high consumption ones. Also, sunlight seems to effect it more than other IR devices.
I'm wondering if it is the 56K part of the device that is causing the problems. Is there anyway to disable it please?
Thank you,
Steve

Posted:
Sun Jan 09, 2005 9:22 pm
by jrhees
Borgs,
Some issues with lots of sunlight or lots of fluorescents can be a problem, but I am trying to determine if what you're seeing is normal or if your unit is unusually sensitive ....
how much does the red LED blink when the lights are on,
and,
does the unit still operate even thought the led is blinking (it should...even though it may generate a fur spurious events which whatever program you're using would simply ignore).
The reason a USB-UIRT will appear more sensitive to random IR interference than your average stereo or TV is because of the fact that it is universal. Your TV and stereo see the same IR, but also know exactly what type of remote IR and codes they're looking for, and simply throw everything else out. They blink their LED when they get a code they recognize as their own.
The USB-UIRT has to accept all IR that looks like it could create a valid code.
-Jon

Posted:
Sun Jan 09, 2005 10:04 pm
by borgs
Jon,
In the office that I configured the machine, the LED was constantly on - so I configured it with the lights off. When I moved it to the lounge, 3 of my energy bulbs have no effect on it but the other makes it unusable - it won't receive a single command. By the way, I have a huge lounge, which is why I have 4 bulbs in it. Unfortunately, the bulb that triggers it is a different fit to the others. I have changed the bulb with one of the same type (all I have at the moment) and it has the same effect.
The office bulb is the same type as the three lounge bulbs. I replaced the office bulb with one that didn't trigger it in the lounge and it still triggered it in the office. The only difference I could see was the shape / size of the rooms - i.e. more reflections.
So, I'm currently experimenting with bulbs - they seem to give off a different amount of IR depending on how long they have been on and some bulbs, even from the same pack, seem to give off more IR than others. It may also have something to do with the age of the bulb.
Sunlight has affected it also, but then, the LED will light up every 10 seconds or so - the unit is shielded from the Sun, and the room never gets very bright, but it was triggering today whenever I walked near it - I could tell that the Sunlight was bouncing off me onto the receiver. I've sent IR to it when the LED has been triggered by the Sun and, so far, it has received all of the codes correctly, although I cannot be entirely sure that the IR command is happening at the same time as the Sun IR blip as, by the time I see the LED light up, the event has probably already passed.
My main reason for the post was to determine if the 56K receiver might be the culprit or whether it was the use of very sensitive receivers. I now understand from your reply why it is not quite like a normal device IR receiver and would trigger more often.
I'll keep experimenting.
Cheers,
Steve

Posted:
Mon Jan 10, 2005 1:11 pm
by jrhees
Steve,
Thanks for the response. It sounds like your unit *might* be overly sensitive. I would suspect it could be the 56KHz receiver. Unfortunately, there is no way to disable it without removing it.
I suspect you may have bulbs with ~50KHz ballasts that are pounding the 56KHz receiver hard.
Please contact
support@usbuirt.com and we'll work through an exchange, etc.
-Jon

Posted:
Sat Jan 15, 2005 6:13 pm
by borgs
Jon,
Thanks for the offer of an exchange. I've since replaced the bulb downstairs with a different type of energy saving bulb and it appears to be working OK with the receiver.
I'm waiting for a sunny day when I am in just to make sure that the sunlight does not affect IR receiving.
If it does, then I will email you at the support address.
Otherwise, thank you very much for your prompt replies and help. Much appreciated!
Cheers,
Steve

Posted:
Tue Jan 25, 2005 5:21 pm
by rich710
I'm too having the LED, blinking and even dont work at all when my bedroom lamps are on. If i switch of the energysaving lamps It works great, took me some time to find out that it was the light in the bedroom that did this, switched batterys in the remote many times ;o)
Found the main problem

Posted:
Mon Feb 21, 2005 9:22 am
by Guest
My videotransmitter "Philips VL1400" is constantly sending out some signals that usbuirt recognize, it's blinking all the time, is there some way to make usbuirt not so sensitive? I know that this really is a Phips problem but dont think they will change their VL-1400 ;o)

Posted:
Tue Feb 22, 2005 5:50 am
by jrhees
Unfortunately, not without destroying the 'universal' nature of the USB-UIRT.
Does the blinking only annoy or does it cause operational problems as well?
-Jon

Posted:
Tue Feb 22, 2005 7:41 am
by Guest
It's pretty annoying, I know I can turn off the LED, but the most problem is that sometimes maybe 1 time in an hour it sends out a signal that turns off a movie that I'm lookin at or do something else with my htpc. Cant understand why the transmitter sends out ir-signals all the time. I know this is not USBUIRTs fault, but just want to let u know if someone else with a Philips VL1400 have problem.