[Elecraft] K3 Sub Receiver and protecting the Sub RX input

[Lyle Johnson]

In general, ensure the coupled energy into the receiver antenna 
connector is less than 1 watt under absolute worst case conditions, and 
preferably under 100 mW, and your receiver should be OK.

Put another way, the antennas should be separated by 40 dB if running up 
to 1 kW, 30 dB if running up to 100W and 20 dB if running up to 10W.  
You might get away with 10 dB less coupling. If you can't get this level 
of isolation by physical separation and/or orientation of the antennas, 
provide some external means of reducing the signal to the receiver input.

Yes, the K3 inputs are tested to higher levels than this, but why stress 
the radio and risk damage to or degradation of the receiver(s)?

If you hear the receiver COR relay click when using the other 
transmitter, reduce the coupling between the antennas or otherwise 
prevent the excess energy from reaching the receiver input.

73,

Lyle KK7P

> ...can you please elaborate on what is sufficient antenna separation when a transmitter is operating on another antenna?