We used to do this back in the mid 70s, we built a VHF receiver (and someone outside in the frost with a big antenna listening to the noise floor and tracking) - the signal was an analog FSK (you can kind of imagine it as a single light sensor and the satellite spinning, getting 1 scan line per revolution) - we'd feed the signal to a TV in a dark room with a manual vertical sync button, and with a camera pointing at it.

As the signal started someone would press the sync button and someone else would open the camera shutter when the pass was done we'd close the shutter and wind the film on, we'd get 2-3 passes a night,at around midnight we'd develop the film.

There was also a much faster broadcast around midnight from a geostationary satellite - 12 images (4 around the equator and 4 around the poles) with the communist countries carefully blanked out, you had to change the scanning rates and be nimble with the camera.

It was fun and the alternative was a close to $1m fax ground station (this was before faxes were something most people had even seen)