[CQ-Contest] New SO2R trick?

Eric NO3M no3m at no3m.net
Thu Dec 6 18:19:35 EST 2018

I've run SO2R in the 160m contests since 2012 at least, maybe earlier.  
Some station details were posted in my 3830 writeup:


2x K3: main rig in diversity RX, one ear always on main focus area (ie. 
EU), other ear scanning directions either on beverages or 8-circle 
array. The second rig used for search and pounce with audio fed to be 
spatially centered in the headphones. Effectively listening to 3 RX 
streams most of the time. Audio routing all done via Microham MK2R+.

Antennas switched via a custom system I designed several years ago, 
allowing scanning, tracking, sharing, etc.

Acom commutator to share AL-1500 amp between both radios with 
independent direction control of the 4SQ per radio.

4SQ TX w/ omni
NE: 3-element broadside beverage array
E,SE,S,SW,W: 2-el broadside beverage arrays
N,NW: 2-element end-fire beverage arrays
BSEF 8-circle (8 directions)


Actual antenna layout can be seen here: 

The 8-circle in the middle is defunct.  It is currently located in the 
front of the property (top of picture) so that there is more separation 
between it and the beverages, providing improved spatial stereo diversity.

I can listen to the guy next to my run frequency in most directions no 
problem (N and NW affected most by transmitting due to close 
proximity).  For weaker stuff, usually OK within 2 kHz or so 
(NE,E,SE,S,SW,W).  K1LT is using a nulling scheme to knock down his 
transmit signal to simultaneously receive, something I haven't explored 
yet but may in the near future.  I just rely on spatial separation.

It is worth doing... I think so.  I had the second highest QSO total 
just 13 behind VY2ZM this past ARRL160.  That's compared to all stations 
that posted on 3830, including the multi-op stations.

73 Eric NO3M

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