[TenTec] Need help from an Orion owner......

[Martin Ewing AA6E]

It's not surprising you see coupling between Ant 1 and Ant 2 ports, at a 
low level.

It's not quite "fair" to test levels on an unterminated antenna port.  
Better to connect an unused port to a 50 ohm load before making this 
test.  It should reduce the apparent coupling. That's because some of 
the power coming in on (say) antenna 1 gets coupled to the antenna 2 
jack and wants to flow OUT of the Orion.  A 50 ohm load will "catch" 
that power.  An open circuit reflects it back into the antenna 2 input.

In any case, the isolation seems to be good enough for ham work.

Another interesting Orion "feature": when you connect only the main rx 
to ant 1, say, you get a certain S meter reading.  If you also connect 
the sub rx to ant 1, the main S meter goes down by about an S unit.  
This makes some sense, since the incoming power is split two ways, but 3 
dB should be 1/2 S unit.

73 Martin AA6E