At 6:38 AM -0500 1/29/03, Eric Scace K3NA wrote:
> A very convenient way to adjust antenna tuners is to use a
>handheld impedance analyzer as the signal source....
This wonderfully convenient method doesn't work for hams who live
near AM broadcast antennas. The definition of "near" depends on a
bunch of factors, obviously; but I can tell you that the 10-kW
1150-kHz TX one mile away and the 50-kW 1510-kHz TX two miles away
from my G5RV completely cream my Autek RX Vector Analyst Model VA1.
A Palomar noise bridge works for me, because my ham RX has plenty of
dynamic range. I wish I had a graphic display that I could use with
the noise bridge. Probably some surplus Elint RX....
Palomar used to make an antenna tuner with a noise bridge built in; I
don't know whether they still do.
An autotuner that used a noise bridge would be nice. I have two
automatic antenna tuners (one built into my Icom transceiver), but
both of them use SWR bridges that require you to transmit at least 10
watts, which very often I don't want to do.
-Chuck, W1HIS
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