[Elecraft] K3 RX Antenna Input RF

[Bill W4ZV]

Jim Cary wrote:
> 
> I seem to be getting too much RF in on my Beverage on 160 when I am  
> transmitting, which appears to be causing the K3 RX antenna switching  
> relay to chatter along with my dots and dashes.  No problem on 80 when  
> using my beverage even though both the TX and RX antennas are the same  
> for both bands.  I didn't have this problem with my other rigs, but I  
> think that is because they grounded the RX Antenna input when the  
> transceiver goes to transmit.  Apparently the K3 does not.
> 
> The bottom line I guess is that I need to either ground the RX Antenna  
> input, or lift it, when the K3 goes to transmit.  Does anyone have a  
> simple circuit that I could use to key a relay off of one of the  
> accessory connector pins?
> 

What serial number do you have Jim?  If it's before about #300, you may need
to install this mod:

http://www.elecraft.com/K3/mods/KXV3_RXA_Board_Installation_Instructions_Rev_B.pdf

"Some operators have very strong pickup of their transmit antenna signal on
their dedicated receive antennas. (Beverages, loops etc.) If the the receive
antenna is not externally isolated during transmit, this energy could feed
back into the K3 via the KXV3 RX antenna in port. Existing transmit
isolation in the KXV3 is sufficient for most installations, but in some
cases additional isolation is needed. The RXA Mod Kit for the KXV3
significantly improves isolation. (This change has been made to revision B
KXV3 main boards.)"

RXA Boards added: Approximately  Feb 20, 2008
Rev B KXV3 Main Board added: March 14, 2008

73,  Bill

-- 
View this message in context: http://n2.nabble.com/K3-RX-Antenna-Input-RF-tp3467294p3467613.html
Sent from the Elecraft mailing list archive at Nabble.com.