[CQ-Contest] CQ and S&P on the same band

[Tree]

W9WI wonders:

> (SO2R does of course force a different strategic decision: which other band 
> will you do your S&Ping on?  Until someone works out the technology to S&P 
> on the same band on which they're CQing.  I'd bet someone is already doing that 
> but hasn't yet released their secret!)  (I've done it in the ARRL DX 
> but only while running QRP)

There is a long history of successful attempts to CQ and S&P on the same band.

I know at least one multi-multi back in the 70's had the ability to split up
20CW into two sections and let a station S&P on each.  This was done with some 
kind of crystal filters I believe.

If you have a couple of antennas spaced maybe 600 feet apart - with some 
directivity away from each other (e.g., two beams with each one off the
side of the other) - you can easily operate on the same band with 100 watts
of power without much QRM.  I have even done this with a KW when using radios
with robust front ends.  

The one requirement for doing this is having some land.  You can't do this on
a city lot.  Another way to do it is to have a remote receiving location, which
is probably getting easier to implement everyday.  However, this technology is 
illegal for most contests.

Recently - I have been doing this on 160 meters, with a KW, using a RX loop with
the null pointed back at my TX antenna - with a spacing of about 800 feet.  I 
think it resulted in a 10 percent increase in my QSO total in the ARRL 160 
contest last year.  

73 Tree N6TR
tree at kkn.net