On Fri, 07 Aug 2009 17:54:16 GMT, "Jerry"
wrote:
"professorpaul" wrote in message
...
Does anyone have design for a log periodic antenna comparable to the
Elk one for 2 meters and 70 cm. I'd like to build one for satellite
work, and with the log periodic, I believe I could avoid the diplexer
issue.
Please respond directly to
Thanks!
/paul W3FIS
Hi Paul
"For what it is worth", I support Jim Lux's advice. A 70 cm Yagii wont
couple much power from the transmitter when sending on 2.meters It would
be easy to test the effect of shunting the 435 receiving Yagii with the 2
meter Yagii. You could even do that with EZNEC.
An antenna like Jim suggests would be easy to build on a broom stick to
test the effects of the 'other antenna'.
The principal value of the Log Periodic is it's bandwidth. That is not
significant when only two discrete frequencies are considered. A
disadvantage of the Log Periodic is it's limited gain. I fail to see where
the Log Periodic benefits the user when only two frequencies are being
considered.
Jerry KD6JDJ
Mechanical and electrical precision.
A single frequency antenna must be tuned very carefully.
The LPDA is "self-adjusting" and easy to make.
And you may change frequency any time.
w.