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IR interference from LCD TV

by crazydud / December 29, 2006 2:43 AM PST

I bought a new Samsung LN-S4692D LCD tv. The TV is causing a lot of IR interference with my satellite HD receiver from dish network. Due to the noise, the HD receiver's remote does not work for the first 30-40 minutes. After this interval the noise reduces and the remote starts working. Does anyone have any ideas to solve this issue.

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Just wondering. How did you measure this noise and ...
by R. Proffitt Forum moderator / December 29, 2006 2:58 AM PST

Can you see said IR in your camcorder?


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measuring IR noise.
by crazydud / December 29, 2006 6:06 AM PST

I did not measure the noise. This conclusion is based on my chat with technical support at dish network and google search. I didnt use camcorder to see any noise.

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It's my secret weapon to find IR transmitters.
by R. Proffitt Forum moderator / December 29, 2006 9:31 AM PST
In reply to: measuring IR noise.

Try it. Look in your camcorder viewfinder and watch the business end of the remote through the camcorder. You'll see the IR pulses (unless the batteries are weak.)

Then you can look around the room for those blinks.


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IR Emissions from newer LCD TVs
by crimipa / January 3, 2009 4:27 AM PST

Some newer hi-end LCD TVs are now using LED backlighting versus more conventional flourescent backlights. I guess the change allows for more control over black levels and lower power consumption.

Apparently when these sets are first turned on from a cold condition the LED backlight power is raised - probably to heat the screen. On my Samsung LN46A850 this lasts about 5 to 10 minutes. After that the level drops and my remote for the Scientific Atlanta DVR becomes useable again.

To Bob's point, this can easily be seen using a more recent video camera, especially one with night vision. During the wee hours a few mornings ago, while it was still dark (I didn't want any sunlight interference), I set my video camera to nightlight and turned on the TV which was at room temperature. Sure enough the screen glowed bright white in the viewfinder. As the picture came on I could barely make out the video image over the bright white. In about 5 to 10 minutes the white background subsided allowing me to view the video image perfectly in my camcorder viewfinder. At that time the DVR remote started working again (I had been checking this periodically while the TV was warming). Camcorders are sensitive to IR wavelenghts invisible to the human eye and display this as white light on the viewfinder which makes them perfect tools to show this problem.

None of this is rocket science and I'm sure the Samsung and other manufacturer's engineers know all this. The question now becomes whether Samsung and the other manufacturers using LED backlights can devise a firmware update that allows us to turn off the warmup cycle or lower the intensity level so that while it may take longer to warmup the TV doesn't flood the room with IR wavelenghts that blind our DVRs and other IR driven equipment.

Please note that this is not just a Samsung issue. Others using LED backlighting have the same problem to varing degrees.


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remotes problems
by Marek1506 / January 15, 2010 12:08 PM PST

thank you for the information,remotes problems started the day I got Samsung 850 so I knew the TV was causing it. DVR uses IR and RF so there I was little confused - RF should help remote to operate better.
Had to point remote to ceiling or floor or wall behind me to make it work.If Samsung will not find solution, one day I will point at TV a special remote control called bazooka which I'm sure will work.
Thanks Paul

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by Eric_Nordman / November 17, 2010 7:07 PM PST

I used to have a Samsung LCD which would show up on my MS mediacenter IR receiver
all the time. I think the problem is that the backlights in a LCD set is driven by an a high voltage inverter, so the backlight is in effect modulated by the frequency that the inverter runs at. This can be seen with the naked eye , but it gets picked up by IR receivers. I now have a gorgeous Samsung LED tv which doesn't put out any interference
as LED's are driven at a much lower voltage and no need for an inverter.

btw, any one interested in a free voice operated remote control , theres a giveaway at

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I didn't know. . .
by Coryphaeus / December 29, 2006 8:04 AM PST

an LCD TV output IR. Since IR is line of sight, have you tried blocking the signal with cardboard? Maybe you can find the specific source. I still didn't know an LCD TV output IR.

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correct me if i'm wrong..
by masterying01 / December 29, 2006 10:18 AM PST

i do not deal with dishnetwork nor do i know how enough to give a good answer....

but arent the remote controls on the hd boxes for dishnetwork radio frequency instead of IR? (i guess it might depend on which one you have. cause i know for sure they have a system where all you need is 1 box for pictures on 2 different tv's)

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Same Problem
by smokn314 / January 29, 2007 1:54 AM PST

I have the same problem with the same TV except I have comcast. I thought it was our cable box so comcast sent two people out and I had 2 new cable boxes and 3 new remotes and it still wouldn't work.

So they took my cable box to another room with another tv and it worked fine so they said its something in the room. So I started trouble shooting and found it to be the TV.

I hooked another TV up on the ground and hooked it up to the box. By just having my Samsung LCD TV on my remote wouldn't work unless I was with 2 feet of the box. As soon as I turned off the Samsung TV it worked fine from anwhere in the room.

Samsung sent a Tech out to look at my TV and said its a known issue and for use to deal with it until they find a resolution. Thats not going to happen, we are working with Circuit city now to excahnge the TV for another Brand.

Just curious how you made out with yours.

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re Same Problem
by crazydud / January 29, 2007 2:19 AM PST
In reply to: Same Problem

I havent found a solution yet, the remote starts working after half hour or we keep it quite close to IR receiver and it works..thats the only workable solution i have found.

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LCD & Comcast
by ticcer99 / January 8, 2008 8:28 AM PST
In reply to: Same Problem

We just got a Polaroid LCT 42" TV and it will work on raw feed TV/Cable setting with the normal TV digital channels. All the Comcast (over 99) are lost. If I turn off the TV, the Comcast box works. Once I turn on the TV, the remote won't control the box, although the box itself will move channels up and down. This seems to be an IR problem. The IR for the Polaroid remote seems to be a wide spectrum and my Comcast box is below the set. Moving it away from the IR area (right bottom front) didn't help. Next try is to mount the Comcast box above the Polaroid. Don't know if it will help, will report back.

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Same issue with Sharp Aquos and Panosonic Plasma
by comtech3 / January 29, 2009 1:28 PM PST
In reply to: LCD & Comcast

I've been a Comcast Technician for 2 1/2 years and I thought I've seen it all. Yesterday we got a memo from our supervisor regarding this problem. It stated a customer purchased a Sharp Aquos and we installed a Motorolla DCH HD Box. The STB remote would not function with the TV on. The tech discovered a feature on this TV (OPC) wich automatically adjusts contrast and brightness to adapt to room lighting. This feature interferes with some set-top IR sensors. The tech resolved the issue by disabling this feature. My last trouble call today was the same issue with a Panosonic TH-58PH1OUKA. I swapped the STB twice and the remote 3 times. Then I noticed that this model has a similar feature as the Sharp, called C.A.T.S. (Contrast Automatic Tracking System). Ok, this is where it gets baffling. The remote functions without a hitch when the feature is ENABLED! Sharp's model has no IR interference when DISABLED. So after 2 hours of troubleshooting I left the customer with a functioning DVR/Remote and a much dimmer picture, because if you manually change the contrast/brightnes, the set automatically enables C.A.T.S. by defult. Panosonic Cust Serv advised me to leave it enabled. There's going to be a hot debate at the shop in the morning on this topic.

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Here is two answers that might help.
by gabereyes / January 8, 2008 11:52 AM PST

Yes LCD TV's can give you IR interference.
Also keep in mind to much sun light in the room can cause IR interference also.

You could try moving the sat or cable box away from the TV, or the best thing to is buy an RF remote like harmony or universal and use a RF to IR convertor that sticks on the front of the box's IR eye this will block out any IR interfernce.

note: the RF to IR convertor from universal can have some problems with time warner box's, but works fine with every one else.

good luck

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W00T !! True Joy !!
by ticcer99 / January 9, 2008 2:56 AM PST

Solved the IR conflict. Easy fix. We had an unused IKEA component cabinet with smoked glass front. Placed the cabinet to the left of the LCD TV and put the set-top box inside. Joy!! Now have a cable box that works with the Comcast remote! Good luck to you all!

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Another Tip or Two
by romertron / January 14, 2008 10:22 AM PST
In reply to: W00T !! True Joy !!

Glad I found this forum. I thought I was the only one with this problem!

I have a Samsung LN-S4692D LCD TV and a Scientific Atlanta HD8300 DVR box (with a Comcast DVR remote). My cable box is on the second tier of a 3-tier entertainment center. The sides/front/back of the entertainment center are open, and the tiers are separated by black glass. The box is about 3 ft below my TV.

The level of IR interference changes based on the Energy Saving feature of the TV (E.SAVING button is 2 buttons below the number 9 on the Samsung TV remote). The Sci. Atl. cable box/remote work best when the TV is set to OFF or LOW Energy Saving. I'm guessing that the emitted IR frequencies at the MEDIUM or HIGH settings are closest to my cable box's IR frequency.

Another work-around is to use a surface-mounted IR extender. (example,, although there must be a cheaper one somewhere) The back of my cable box has a port labeled "IR" (1/8"). One end of the extender plugs into that port, while the other end is placed over the cable box's IR receiver. An extender came with my Bose system and it allowed me to operate the cable box from ~8 feet. However, I've taken it off because the remote/box work fine when I have the right Energy Saving setting.

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Same Problem with Samsung
by rcwis02 / September 24, 2008 10:03 AM PDT
In reply to: Another Tip or Two

I have the same problem with the Samsung LN40A650. Called Samsung tech support and they acted like they never heard of the problem. Anyway, its definitely an IR problem caused by the TV.

I see that Amazon has the Next Generation Remote Control Extender. Looks like that should solve the problem although I haven't tried it.

Good luck.

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Turn Off "Brightness Sensor" on TV
by LCDfan / February 18, 2009 10:21 AM PST

i had the same problem with Samsung LN-409D (LCD) - i got a new DVR (Motorola DCH 6416) from Charter, with a "Universal Electronics Charter OCAP 4-Device Remote Control" - the DVR seemed to work fine until i turned on the TV - then it was essentially dead for about 20 min, then started working again.

I went into the TV menu > picture > brightness sensor > off.

(the brightness sensor just varies the brightness of the TV based on level of ambient light)

this fixed the problem - i can reproduce the problem by turning the brightness sensor back on, so i'm pretty sure this is no random variance.

i can live without the brightness sensor - if your TV does not have a brightness sensor option, then i'm not sure what works, but maybe try turning off various picture options and see if that works.

hope this helps.

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You saved my day!
by fbacklund / September 25, 2009 11:02 PM PDT
In reply to: Another Tip or Two

Just invested in a Samsung LE52B755 and was confronted with massive ir problems. By turning off the energy saver the problem was gone. HALLELULJA!!! What would one do without internet. Thanx again. Fred

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Dish Network DVR IR Remote wont work with Sony 52" LCD TV -
by usfjx / June 14, 2010 3:47 AM PDT
In reply to: W00T !! True Joy !!

Hello all
I have been living with this for years.
Here are a few things that will solve the problem.
1) Place black insulation tape around the IR in window on the DVR to shield it from the LCD TV
2) place a reflective shield (like aluminium foil) above the DVR to shield it from the LCD TV
3) Place DVR as far from the TV as possible to shield it from the LCD TV
4) Place DVR in a cabinet with a smoke glass screen to shield it from the LCD TV
5) Turn on Halogen Lights above the TV and DVR (this negates the interference from the LCD TV
6) open the windows - works better in daylight (see 5 above)
7) worst case scenario - change channel by pointing Remote directly into the DVR IR window.
Kind wishes

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IR Interference LCD TV
by feelgoodalso / July 14, 2008 10:06 PM PDT

I had the same problem. I bought a "Wired IR Remote Receiver/Repeater (Kit #RRIC @ $29.95 and 100VAC Power Adapter #AC125 @ $9.95) from Ramsey Electronics ( 800-446-2295. I assembled the kit. The face of the box has a IR signal receiver and a (Green LED) that shows IR activity received by the box. The unit then transmits, by wire, the received IR signal to a white LED tip that you place in front of (on) the DVR IR window using black electrical tape to hold it in place. The box will receive your remotes signal and place it directly into the DVR IR window. This signal is much stronger than the stray IR from the TV. IT WORKS GREAT. It is interesting to see the green LED on the box start to flicker when you turn on your TV and other lights in the room. Interfering IR is everywhere but as you know the LCD TV generates a lot. If you have any questions about my fix don,t hesitate to email me. Also Ramsey will talk to you about the kit assembly if you have problems.

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by robinhood1331 / October 1, 2008 2:09 PM PDT
In reply to: IR Interference LCD TV

"The back of my cable box has a port labeled "IR" (1/8"). One end of the extender plugs into that port, while the other end is placed over the cable box's IR receiver."

Not really understanding that part. Can i use this if its just the cable box and the tv? Sorry for bringing up a old topic but this seems to be a problem for me as well Sad

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remote booster
by katzzer / November 13, 2008 2:45 AM PST
In reply to: IR Interference LCD TV

I'm considering using the Hotlink remote control booster,

The components, cable box, etc. will be in a closet behind the wall mounted LCD TV. The sensor can be placed anyway but I'm thinking behind the TV facing the wall. The theory is the it'll amplify the IR beams. I'm thinking the transmitted IR should then be strong enough to over ride the emitted IR from the set...any thoughts as to the sensor placement or other suggestions.

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Toshiba 46V530U TV and Cable Box Remorte not getting along
by T om Wendel / January 23, 2009 11:22 PM PST
In reply to: remote booster

I have the same problem with my Toshiba 46RV530U TV and Scientific Atlanta 8300HD cable box. I thought I was crazy and Toshiba Tech Support was no help. Tried turning off the power saving function, and tape over the cable box, neither worked. WHAT DID WORK was turning the cable box on about a 45 degree angle facing away from the TV. That has seemed to have solved the problem. Very frustrating. If I hadn't found this forum I would still be shaking my head.


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Toshiba 46xv640U and dish HD receiver not getting along...
by vaas72 / November 17, 2010 1:20 AM PST

Hey Tom,

I'm having a similar problem with my new Dish HD remote and the dish tech told me this could be a prob with the IR. However after reading this blog, I wanted to turn the energy saving option to low of off on my Toshiba, but could not find that feature/option anywhere..Can you tell me where if on tv or tv remote will I see the option to turn this off??


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by jcruz1st / November 17, 2008 4:35 AM PST
In reply to: IR Interference LCD TV

same problem same tv i messed with energy saving button it works better little slow but better

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Same problem easy fix.
by deadguy_366 / February 11, 2009 1:32 AM PST
In reply to: IR Interference LCD TV

I have a sharp aquos and a shaw HDPVR and had the same problem until I realized it was my TV causing the interference.

You don't need a 1/8 IR repeater thing. (one came with my box)
You don't need a ridiculus cardboard tube.

You just need a piece of tape (scotch will work).

There are usually two infrared eyes on the front of a cable/satellite box. One to recieve and one to transmit signals. Be sure to tape over the one that transmits. ( a little experimenting can determine this.) Through a small amount of trial and error you should have your remote working perfectly in no time.

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Simple Solution
by rahermes / June 29, 2011 11:06 AM PDT
In reply to: Same problem easy fix.

Scotch tape worked with an LG TV and Dishnet! Thanks.

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IR Interference from LCD TV
by powertraxxx / October 23, 2008 5:39 PM PDT

What an informative post. I have a samsung ln52a650 and motorola comcast hd box. Initially my remote always took a minute or two before it worked consistently. I was playing around with my tv settings at the time so I didn't notice a correlation. Recently my hd box would barely respond to the remote. After reading this post I remembered I changed the ENERGY SAVING settings to med or high. Switched it back to low and now everything is OK. Never would have thought, thanks for the info!!!

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Energy Saving
by Chris_L1234 / October 31, 2008 9:47 AM PDT

You're my hero. I turned off energy saving and the remote works perfectly. 3 months of living with a whacked out remote, all over one stupid setting!


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A simple solution to IR interference.
by PeteLetch / November 23, 2008 12:41 PM PST

I recently had AT&T U-verse cable installed, and I discovered the same IR interference noted by others in this forum. I had to hold the remote within inches of the receiver box for it to work. I found a very simple solution to this problem. I took a toilet paper tube and spray painted it black inside. I then positioned the tube with one end over the IR receiver window on the box and the other end pointed towards me. From then on the remote works perfectly. I can only assume that the tube blocks all extraneous radiation from hitting the box, and only the IR signals from the remote go into the tube.

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