KH7T:
>On my Orion, I measured the following isolation between antenna ports 1
and 2.
I fed Antenna port 1 with an HP generator with a calibrated attenuator.
I set the signal at S9.
Then I switched to Antenna 2 and increased the signal level until I got
S9 again
28.5 MHz, 40 db, Antenna 2 open
3.888 MHz, 45 db, Antenna 2 open
3.888 MHz, 50 db, Antenna 2 terminated with 50 ohms
Very consistent with ARRL's Expanded Test Report below.
73, Bill W4ZV
Test Description: This test measures the RF isolation between the
active (selected) antenna port and the other available antenna ports.
This isolation can be important where the unselected port is
connected to an antenna that is resonant (or near resonant) on some
of the same frequencies as the main antenna. Isolation of 60 dB or
better is considered good.
Test Results (isolation at 14 MHz):
ANT 1 selected ANT 2 unselected - 42.3 dB
ANT 2 selected ANT 1 unselected - 51.4 dB
(from ARRL Expanded Test Report on Orion page 15)
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