[Elecraft] KAT500 Signal Isolation between antenna ports

[Phil & Debbie Salas]

Hi Keith – Take a look at the measured KAT500 isolation numbers in the “Product Reviews” section of my website at www.ad5x.com.  The isolation varies based on the ports chosen, and the frequency band.  As an example, the isolation on 20 meters has a worst-case value of 36dB between ports 2-3 (when 3 is selected), and a best case value of 65dB between ports 3-1 with port 1 selected.  You might want to select the antennas and ports to maximize isolation.  As an example, port 1-2 isolation is much worse than port 1-3 isolation.  So I put my 6-meter beam on port 2, and my two HF antennas on ports 1 and 3.

You can easily hear signals that are very far down from a desired signal.  Measurements made in my old telecom days indicated that you can usually hear tones as low as 90dB down!  And, of course, if the signal on the unselected antenna is hotter than on the selected antenna, things can sound worse.

Phil – AD5X