Atari 65XE Owner's Manual page 11

75-OHM round variety with a screw-on connector, attach it to the
threaded 75-OHM connector labeled ANTENNA on the side of the TV
Switch Box.
If the antenna cable is a flat twin-lead 300-OHM cable, attach it to the
300-OHM screw terminals on the side of the TV Switch Box.
2. If your television has a threaded VHF connection, attach a threaded
VHF adapter to the twin-lead cable labeled TV at the bottom of the
Switch Box and attach it to your television. (The adapter should be
supplied with your television; if not, you can buy one at a video or
television store.)
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