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

[Don Wilhelm]

Phil,

The K3 ANT1 and ANT2 connections are not of concern, they are protected 
by the T/R circuits in the K3.

The AUX ant is protected by a COR (Carrier Operated Relay) that will 
activate if there is too much RF being brought in by the AUX antenna.  
While it should protect the K3 (and KRX3) from damage, you will hear the 
COR clicking as you transmit.
If you do hear such relay clicking, the "cure" is to move the RX antenna 
further out of the field of the TX antenna, or provide some form of 
external 'protection' such as shorting the RX antenna input during TX or 
alternate means of disconnecting the RX antenna during RX.

73,
Don W3FPR

On 1/27/2015 4:41 PM, Phil Anderson wrote:
> Perhaps you could clarify protection on RX inputs. I have the KRX3 and 
> run the internal 100 watt amp.
> Sometimes I share the same antenna with TX,  ANT 1 or ANT2. I assumed 
> there that the RX is protected.
> Sometimes I use the AUX antenna for diversity receive. Is that input 
> not protected? When does it need to be?
>