About a year and a half ago we got ourselves a new television. Everything worked fine for a few months. Then, all of a sudden, the remote starts acting funny. Some of the buttons don’t work or only work sporadically. Finally it settled into a state where certain buttons don’t work at all and some are fine. Occasionally the remote shows signs of life, but not often.
Mostly this meant we couldn’t change channels via the remote, but we mostly changed channels through the VCR anyway, so we dealt.
Anyway, being pretty sure it’s the remote that’s the problem, I manage to get a replacement remote and all is good. Until a couple of days ago when the new remote stops working. Most of it anyway. Again, some buttons work some don’t.
On a hunch I put the batteries from tis remote in the old one and its working fine.
Possibly some interference in the room. Take one of the remotes that’s not working. Make sure it’s not working, then bring it up to the TV hold it right near the IR receiver and use your hands or something to block everything else out, then try it. If it works, it’s just a matter of finding the interference. 75% of the time, it’s another remote stuffed in the couch cushions with a button being held down.
If you have a digital camera or webcam, you can use it as an IR detector to help diagnose the problem. Most CCD- and CMOS-based image chips are fairly sensitive to the near IR that remotes emit. If the remote appears to be emitting a signal when the buttons are pressed, but the TV does not respond, it could be interference with another IR device (which you can also use your camera to locate) or there is a problem with the TV itself; possibly the little window over the IR receiver is dirty or the circuitry inside the TV is acting up.
In addition to what **Trion ** said, I’d check to see if the IR receiver on the TV has a bright light shining on or near it. Most lights emit IR as well as visible spectra. Some movement sensors for use with burglar alarms also emit IR. See my patented IR spotting method below.
Some TV remotes use a pretty clever protocol called IRDA and some use a simple flash ‘n’ times to signal. If you have a simpler style, it could be easily jammed by a bright light source which is also emitting infra-red.
And for the geeks amongst us you could try finding somebody who has a camcorder with a NightShot mode (most recent Sonys do - I assume other brands too). Simply turn the camera into NightShot (which makes it IR sensitive) and cover up the IR emitter on the camera (easy way to find the camera IR - turn all the lights off go into NightShot mode and point the cam at a light painted wall. Cover parts of the camera with your hand until the display dims).
If you use this to look around the room, anything which is emitting IR will appear to glow - try looking at your remote when you press a button to get an idea of what I mean.
You don’t need a fancy camera with any sort of night shot mode or whatever. A regular cheap digital camera or webcam will detect near IR quite well,a s I already noted. All night shot mode does is turn on a bunch of high-brightness IR LEDs to illuminate the scene–the CCD or CMOS chip isn’t anything special. Static illumination from incandescent lamps will not generally affect the remote, although direct sunlight sometimes can.
I’m not wanting to pick a fight here, especially with a member of the SDSAB, but
I understand that night shot (in some instances) disables an electronic filter which would ordinarily cause IR to be filtered out. I have a Sony DV camera here and if I point a remote at it in “normal mode” the IR isn’t visible. If I enable IR sensitive mode then the remote flash is visible.
I did read about this a while ago and it was suggested that due to the increased sensitivity to IR from CMOS and CCD devices, manufacturers commonly employed an IR filter - often a plastic gel but in the case of this DV camera, an electronic filter.
Without this the recorded image would be over-bright due to the effect of (human) non-visible IR being registered as visible light on the IR sensitive CCD/CMOS.
So, whilst both methods can achieve what we suggested, I would suggest that a “night shot” mode is often more than simply super-bright IR leds. I also realise that this reply borders on pedantry, so I’ll shut up now
This site explains how to remove the IR block filter from a cheap-o webcam.
I’m not sure how tech savy you are so if this sounds overly simplistic of a solution I don’t mean to talk down to you. It’s just that I have solved my parents, in-laws, and many customers “my remote doesn’t work anymore” problem with this.
Many remotes (even those supplied with your tv, vcr, cable box) are set up to control appliances other than the one they came supplied with. (i.e. Your Sony TV remote that came with your Sony TV will also control a Sony VCR, Sony DVD player, etc.) These remotes usually have a row of source buttons (look at second row).
The remote will control your TV just fine. But if you press, or accidentally press, the DVD button the remote is now set up to send signals to a DVD player. It won’t control the TV anymore. Not until you hit the TV button again.
Simple (doh!) solution but it has solved 90% of my customers problems.
Hampshire, I can tell you that wasn’t the problem with the original remote. The volume controls and the channel controls formed one big circle in the TV control section. WHile the volume worked fine, the channel did not. The problem with the second remote was so similar I didn’t think about that solution despite the entire “circle” not working.
I did find the IR window on the TV.
I just went to check everything out and both remotes are working perfectly today. I saw the IR output from both remotes through the digital camera, so I know what to look for if it happens again.
I’m not sure how an electronic IR filter could even work - once the cmos elements have been excited by photons, the image is just electrical charges and there’s no way to tell whether the photons that caused it were the right colour band for the sensor, or if they were IR (to which all of them are sensitive, regardless of their visible-light specificity). I can well imagine that a camera might have a physical IR filter that it can withdraw for nightshot mode, or even that it just increases the gain in general, but if there’s such thing as an actual electronic (of firmware) IR filter, I’d love to know how it works.
I used a webcam for my birdbox camera, illuminated by two LEDs stripped from old TV remotes - I did remove the little IR filter gel, but even before I did, the camera was pretty sensitive to IR.
My guess is that the cameras with a controllable IR filter do it by electromechanically moving an actual optical filter (which all consumer CMOS and CCD cams have) in or out of the optical path or some similar mechanism. It might be called an electronic filter, but that’s probably misnomer.
That sounds most likely. I suppose it’s also possible (in theory, at least) to have some kind of device (a form of LCD, perhaps) that is optically clear in the visible spectrum, but variably clear in IR, depending on an electric current. Not sure whether any such thing exists though…
(bolding mine) On remotes I had that controlled both the TV and the VCR, when the remote was set to control the VCR, the volume buttons still controlled the TV volume. This is because the VCR doesn’t have its own volume control.
IR spotting method below.
