Sega Master System II Instruction Manual page 7

TV with connected video cassette recorder
ee French Model)
; 50
TT o_o
BACK VIEW OF POWER BASE To RF Jack
RF Cable
Video Cassette Recorder
Switch Box Antenna Cable
BACK VIEW OF TV SET
(75 ohm)
If a video cassette recorder is 1. Disconnect the video cassette
already connected between the recorder cable from the
antenna and the television's television's VHF terminal. Then,
terminal, use the RF Switch Box. plug this same cable into the RF
Switch Box.
2. Now, plug the Switch Box
Antenna Cable into the TV.
3. Connect the RF cable between the
RF-Switch Box and the RF Jack on
the back of the Power Base.
4. Finally, set the RF Switch to
"COMPUTER' position.