I Built the 10m Sleeve Antenna
wrote in message
ups.com...
On Feb 22, 12:16 am, "Sal M. Onella"
wrote:
It was a bust. :-(
They can be quirky..And the decoupling is pretty critical. I always
preferred
a base fed half wave for those reasons. You still need to decouple for
best
performance, but there are no "coax in the way" issues, etc.. I use a
simple
"gamma loop" feed. IE: single turn coil, and a cap if needed.
Sometimes
you don't need the cap, but if you do, 30-50 pf is about the usual
value for
10m. I make those from a short length of coax.. I'm basically copying
the
feed system of the usual cushcraft ringos.. BTW, cushcraft sells a 10m
ringo if one doesn't want to build one, or have the tubing.
I will try decoupling and also try that feed.
I have several commercial antennas but I tend toward building them myelf. I
learned the hard way about the three types of copper pipe, K, L, & M. Until
I got home and hit google.com, I didn't know to shop for the more economical
Type M and paid premium $$$ for Type L. I don't want to think what Type K
would have cost.
"Sal"
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