Multi Input IR Remote Control Repeater

[Peter]’s folks’ cable company is terrible – such a surprise for a cable TV provider – and the digital part of their cable subscription will only work with the company’s cable boxes. The cable company only rents the boxes with no option to buy them, and [Peter]’s folks would need five of them for all the TVs in the house, even though they would only ever use two at the same time. Not wanting to waste money, [Peter] used coax splitters can take care of sending the output of one cable box to multiple TVs, but what about the remotes? For that, he developed an IR remote control multidrop extender. With a few small boards, he can run a receiver to any room in the house and send that back to a cable box, giving every TV in the house digital cable while still only renting a single cable box.

The receiver module uses the same type of IR module found in the cable box to decode the signals from the remote. With a few MOSFETs, this signal is fed over a three-position screw terminal to the transmitter module stationed right next to the cable box. This module uses a PIC12F microcontroller to take the signal input and translate it back into infrared.

[Peter]’s system can be set up as a single receiver, and single transmitter, single receiver and multiple transmitter, many receivers to multiple transmitters, or just about any configuration you could imagine. The setup does require running a few wires through the walls of the house, but even that is much easier than whipping out the checkbook every month for the cable company.

Video below.

23 thoughts on “Multi Input IR Remote Control Repeater

  1. Very nice! The only way this could be better is if it used a single board that could be populated for either receive or transmit, which would make it easier/cheaper to buy in bulk.

    Depending on the specific use case, no extra wiring is needed if you have unused POTS cabling in all the required rooms. Just make sure the house is disconnected from the telco’s box.

    1. In the UK, most non-free TV is typically from Sky Satellite. The digital receiver box has extra RF outs for running coax to TVs in other rooms.

      If you buy a ‘sky magic eye’ or ‘sky magic remote’ it sits between the coax and the TV and allows you to send IR commands back to the box over the existing coax.

      Here’s a picture of a generic version of that device that I used before –

      1. I was thinking this. The sky boxes even put power over the coax that the magic eye uses. He could try to encode the ir signal and send it over the coax and filter it out at each end, but a pair of 433mhz modules is probably cheaper.

        I guess he is taking the modulated analogue coax output of the digital cable box and splitting it to route over coax though the house to TVs which demodulate the signal and convert to digital to display on the LCD. Perhaps the worst way to distribute digital TV I can think of. Its not 1992!

    2. Xantech’s IR extender system supports multi-in/out over the same coax carrying the video signal. Their IR receivers are pricey, but their CPL-10 coupler which injects/extracts IR signals to/from the coax is around $10 on eBay. I bet [Peter] could use those somehow with his IR receiver and senders.

    1. According to the instructable, they have two cable boxes. So I guess one cable box is split between X number of TVs and the other is split between Y number of TVs.

      So the answer to your question is that it depends which room you’re in. Unless he’s split the coax from each box to every TV in the house.

      1. That is correct there are 2 boxes with the TVs split between them. Just happens to work out that mom primarily uses 3 of the TVs and Dad watches the other two. Thought about some sort of switching matrix and / or remodulating the catv signal from one box to another channel. But in the end it was a lot more work for not much gain.

  2. These have been commercially available for decades. Nowdays you have far more capable control with many of the Comcast boxes having smartphone control.

    Putting the cable boxes in the basement and using an AV distribution has been the norm for many homes… I installed my first one back in 1995 with IR control and routing. Nowdays you have RF touchpanels and phone+tablet control. along with your bluray, roku,etc all in the basement AV rack.

    Lastly there is a cheap system you can buy that can send the IR signals back down the Coax cable. they work well but do not give you any routing capability.

    1. Exactly. IR repeaters are available for roughly $20 off eBay:

      I doubt you could build something that works as well as that does for less money. These also have the advantage of working in the modulated domain — not the baseband domain — so they work with a wide variety of IR frequencies and devices. Boom.

  3. It looks quite like ‘one I made earlier’ (14 years earlier :-) ), which does the same but uses the venerable / overused / irreplaceable 555 timer at the transmit end – . And I know it works as it’s been used every day since!

    The IR devices are cheap and readily available (they weren’t in 2000, we had to arrange a group buy for the 100 MOQ), and it’s simple enough to make as a useful first project for beginners on veroboard, but I like this as a nicely packaged alternative.

      1. Its not that “I want it” but more of a “you stated code would be in zip” also it would be extremely helpful for people to learn. I have done so many IR projects. I cant name them all but that doesnt mean i wouldnt like to see how someone else writes their code :) Just more of a CURIOSITY type thing :)

        1. Thanks much the Tymkrs and the rest of the rabbit hole crew will be glad to hear it. It’s fun to hang out and help folks although I don’t seem to get much done on my projects :) Made up a extra set of kits for them to sell similar to the LED candle simulators. Good chunk of the profit goes to help support the Rabbit Hole (the hacker space not the video :)

          1. Tymkrs are awesome. I talked to one or 2 on irc. Saw your pumpkin video as well. Pretty cool. I might do that this year and have my 7yr old son help :) thanks for posting and the blog.. its awesome… keep it up.

  4. I would think that the bandwidth requirements of the demodulated IR signals are pretty low…why not skip the additional wiring and just hook the PICs to a 434 or 915 MHz RFM12B or similar.

    1. Would probably work but already had a easy way to string the wiring and this keeps things simple. Folks are 4 hours away from me so wanted to avoid any “TVs are not working” calls in the middle of the week.

    1. Since the cable boxes were dedicated to TVs I also dedicated the IR loops to those boxes. So the IR receiver in the kitchen repeated to the IR transmitter next to the cable box that drove the kitchen TV. A little bit of cardboard between the boxes keeps the IR signals meant for one box from affecting the other.

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