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Well there are only two IR codes for the H21's (00001 and 00002), so you would have to program all four for RF or two for IR and the other two for RF.
To set them up you need to go to the menu/setup/remote and change it to RF and than follow the instructions for each unit and it will give you the code.
As for the TV's the only way to do is if each TV is a different manufacture you can program each one into a different remote. If they are all the same manufacture than they will all be controlled together.
Well there are only two IR codes for the H21's (00001 and 00002), so you would have to program all four for RF or two for IR and the other two for RF.
To set them up you need to go to the menu/setup/remote and change it to RF and than follow the instructions for each unit and it will give you the code.
As for the TV's the only way to do is if each TV is a different manufacture you can program each one into a different remote. If they are all the same manufacture than they will all be controlled together.