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More patch results.

Listened tonight on my BBQ dish with a homebrew passive feed around MA 
160-190. I don't know if something has gone south in my receive chain with 
the old DEM preamp and converted Drake, but AO-40 wasn't that strong.  
Beacon was about a S-unit and a half above the noise.  SSB was barely 
readable, CW was okay.

Switched to a 3.5 turn Helix on the DH Satellite 4' center fed dish
Got about a S-unit and a half increase in signal.

Tried the patch I built with the coaxial feed on the "near diagonal" and got 
another S-unit or so of signal, but to my unscientific ears, the S/N sounded 
better on the patch more than the one S-unit increase.  I tried the other 
polarazation sense on the patch and the sigs were a S-unit or so down.

S-units were on a FT-847.

This was very unscientific.. I don't know if you've all see the original 
"Mode-S: The book" by K9EK, but I was doing the manual handling of the dish 
and feed like the "wok" that Ed used in the picture in the beginning of the 
book.... but with a four foot dish!
So it was hard to hold everything at the peak of signal strength and tune 
around.  I'll have to build up a mount in my "spare time".

I think the patch works, and a bit better than a helix for a feed.  It's 
much easier to construct and get a good match on.

I was a bit disconcerted about the signals I were receiving. They should 
have been better.  Anyway, for the purposes of testing the patch, the 
relative readings were good.

Fred W0FMS

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