[Elecraft] RE: Request for info - integrating 2 K2s to achieve "2ndRX" capability

[Geoffrey Mackenzie-Kennedy]

George,

If using separate antennas and to protect the front end of your K2's 
receiver from RF generated by your K2/100 radiated by its antenna, you might 
want to consider adding an external relay at the K2's antenna input 
controlled by the EXT AMP KEY line of the K2/100. Although I have not looked 
at the timing sequence of this line in the K2/100 it should be such that 
anything controlled by it is 'ready and waiting' before RF appears from the 
K2/100's Tx output. I am certain that other people on the List would be able 
to comment on this. The external relay would be used to disconnect the K2's 
antenna from the K2's Rx input and ground the Rx antenna input, and should 
be a fast acting type such as a reed relay..

Back- to- back diodes as protection devices should be avoided in a strong 
signal environment at any point in a receiver chain unless increased 
intermodulation problems are acceptable. The increase in IMD problems that 
these diodes cause start well before they are fully switched on by incoming 
signals.

73,
Geoff
GM4ESD



On Thursday, April 19, 2007 at 9:40 AM, George G4TPV wrote:

I have acquired a 2nd K2 (via a rally sale) so now have my K2/100 main rig 
plus a K2 "QRP" rig.
One set-up that I would like to try is using the 2nd rig as an integrated 
2nd receiver.
It has "RANT" & I can use separate aerials (antennas) - any advice/cautions 
would be welcome. I absolutely don't want to destroy anything in either rig 
!

Note : I have never owned or used a "high-end" rig with this in-built 
capability

73

George G4TPV