Input to the A/B antenna inputs are TR switched to the RX via relay RL
1002.
If external RX antenna is selected in menu, the TR switched RX line from
A/B
antennas go to "RX out" rather than to the internal receivers while the
"RX
in" is switched to the internal receivers.
If normal RX is selected in menu, the RX in and out go nowhere.
http://www.wz5q.net/index/manuals.htm