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Old August 30th 06, 07:56 AM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 2,951
Default Log Periodic ant

On Wed, 30 Aug 2006 06:19:09 GMT, "Lee"
wrote:

I have a wide angle lens (low gain) it`s known as a discone !!!
freq range to 3000megs,


Hi Lee,

Simply because it has a "frequency range to 3000megs" does not mean it
is usable to 3000megs - only that it matches to 3000megs. Matching
and usability are not strictly related.

supposedly 0db ref dipole that has heard one
or two weak signals just outside its range


Antennas don't have "ranges." You may experience poor performance due
to the combination of transmit power, path loss, and receiver
sensitivity, but none of this has anything to do with the antenna
(unless its poor construction adds loss). If you have too much path
loss, not enough transmit power, or poor receive sensitivity, then,
yes, a gain antenna will make up for those problems (as long as S+N/N
is sufficient in the end) - but this still does not confer a range
specification to an antenna.

This would be whole lot simpler if you simply told us the model number
of this discone.

If i knew how to scale or re-engineer an existing design, i wouldn`t be on
this NG
asking how to do it ...


You don't offer enough parameters like frequency span, gain, F/B, how
long a feedline, what kind of feedline (lot of potential loss there)
for someone to whip out a design here, and that wouldn't be a modest
enterprise if you did. Scaling is the easiest solution, perhaps you
should buy a log periodic. Google would be another solution, your
problem would not be unique - would it?

73's
Richard Clark, KB7QHC