Steve Hagar wrote:
>
> So far all of the antenna guides I have seen note the installation of
> the ferrite "baluns" on the antenna lead going to the dipole. This to
> reduce the reflected power going down the lead. I am getting ready to
> stuff an Archer antenna up in the tailfin before bonding the top and
> bottom halfs together. The instructions for the Archer do no detail the
> installation of the toriods. Since this installation is inaccessable
> once everything is together I was going to install these items on the
> cable anyway. The queston is has any one had to do this to reduce
> reflected power on the Archer? In addition, is having the toroids on
> the cable in any way detrimental to the performance of the antenna if
> there is not a reflected power issue?
Mr. Archer does not believe in ferrite core baluns, as he says tests
in his RF lab show they don't do anything for his antennas. The bible
(ARRL Antenna Handbook) indeed explains that the most to be achieved
is predictability in radiating pattern in an idealized environment,
which one won't have in an airplane due to the effect of nearby metal
elements particularly on a dipole. IOW, trade one sloppy pattern for
another unpredictable one. If your concern is pwr reflected back into
the transmitter, it basically won't know whether the cores are
installed or not.
Regards,
Fred F.
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