Please stop SHOUTING! All caps is very hard to read.

The only practical methods are to build the RF2RF adapter or to add a small RF transmitter and signal conditioning board inside the remote. I've already provided links to web pages with full details for RF2RF adapter and for modifying the TS1000 and TSU2000. The method will be similar with the RC5200 but I've never seen the board inside an RC5200 so details may be different.

Please read the web pages referenced before asking questions that are already answered there. My health is very bad and I don't have a lot of time to waste.

It is not practical to modify the X-10 receivers. Anybody with the type of electronics laboratory equipment needed would not be asking questions like yours.

You could build a BX24-AHT with a 418MHz RF receiver but you would have to get the board made yourself as they are no longer stocked. Those details are here...

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