The Philips PM5680 is a professional TV modulator where an RF board can be added so that it can be used as a TV transmitter.
The video input board.
The video processor board.
The video modulator board.
The single side band module.
Video RF output board.
Sound modulator board.
The actual HF transmitter is tuned to channel 33.
The complete device.
The image goes through two layers of concrete and you don't need an antenna.
Frequency spectrum with sound.
Frequency spectrum without sound.
