Phill's old radios sum's up what it takes to run a blonder tongue well.
https://antiqueradio.org/HomeTVTransmitter.htm
I've got 4 BTs set up, and I could use a computer to feed them continuous video, but I don't watch much on a regular schedule so I just manually que up whatever I want or leave my cable box feeding them. Right now my main system can take video from a PC (I have both an old graphics card that has an S-Video output and an HDMI TO AV converter hanging off the DVI/HDMI output), cable TV, 3 digital video disc formats, 2 analog video disc formats and no less than 3 video tape formats...And a partridge in a pair tree.
My secondary system has a few less formats but all my videogame consoles hooked up...