If you're getting a good signal in your area, then a proper splitter would probably do the job well. The DIY shops do two gang Rf sockets which you can use to take your existing antenna coaxial cable into, then use two fly leads of normal TV gauge coaxial cable from it to the two tele' sets. Fit it on the wall with a surface mounted box and off you go.
If you've got a really strong signal, you can simply use a splitter to feed the signal to 2 sets without additional amplification.
If this doesn't work satisfactorily, you need an amplifier with one (or two) inputs and at least two outputs. Wickes had used to sell some good ones - made (I think) by Labgear.
If you have a VCR with the first set, and wish to have the option of playing this back through either set, connect the downlead from the aerial to the VCR input. Connect the VCR output to the amplifier input. Connect one amplifier output to the first set, and another to the second set.
If your amplifier has multiple outputs (mine has 6) you can cable it up to various points (bedrooms etc.) where you *might* want to operate a TV at some future time.
If your amplifier has two inputs, the second one is for VHF (FM) radio. If you connect an FM aerial to this, you can also distribute FM radio throughout the house. You can connect either a TV or a radio to each amplifier output - or both with a suitable splitter.
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