K3 2nd external RX antenna. Today's VK7DIK 80m index is 3...against 1 yesterday..

When using the K3  KVX3  RX ANT IN  and RX ANT OUT for the 50MHz preamp.  The lowband receive K9AY loop antenne had to be disconnected. 
But i think there is a  work around for this problem.
I now use the AUX connector to the K9AY for the 2nd receiver.
When the SUB is switched in. The audio Left channel is the main and right is the sub. The AF SUB Volume control is balance control for diversity receiving over 2 different antennas.  The SUB can be switched to AUX or MAIN ANT. So if the sub receiver is locked to the main and the ANT is switched to AUX i can use the K9AY connected to AUX.
For WSPR i need to set the recorder mixer ruler to the right to have only the loop audio or to left to have the main antenna signal. Or i the middle for a mix.
Would be nice if the line in left/right audio balance was also controlled by the SUB -AF knob but it seems it is not. I did set the mixer line-in ruler to the right and than switch of the Loop and i see a level drop.  I did not see this level dropping when setting the ruler neutral and turn the SUB-AF max right.
I  have to inquire the K3 forum for this issue. reading the manual will not help much for this details.
It seems this way i can use both the 6M preamp or also a transverter and still i can use the 2nd receive antenna over the AUX of the SUB receiver.

I am testing this now to find out if this will bring better receiving on top band in WSPR mode.  
Tonight propagation on 80m is better again.
The 80m VK7DIK index is 3   against 1 yesterday....

The 50MHz CN8LI index is 6  yesterday 1 decode only