So we're selling our old sylvania projection telvision, from 1990. while browsing the manual, I spotted something odd.
there was an 'rf switch' accessory for the television. (we never got it, but the port was there; a weird DIN5 sort of connector on the back.)
the picture shows the rf switch connecting to the odd port, and 3 coax inputs from 3 devices: a VCR, a 'video disc player', and a 'video game'. the pictured 'video game' looks like an odyssy2.
I'll have to find a good scanner and upload pics before it gets sold

was sylvania just a label of Magnavox, or were they separate from them? if the latter, how'd they get away with using the o2?