In article ,
"Marcus Tait" wrote:

Hi,
I have just been tuning a 400MHz 1/4 wave antenna (approx 170mm length of
wire). I connect a receive antenna to a spectum analyser and the antenna to
be tuned to the signal generators 50ohm output. I set the signal generator
to 400MHz and adjusted the length of the antenna to get a maximum peak on
the spectrum analyser. My question is when i have tuned the antenna for
maximum output at 400MHz is the antenna then tuned to 400MHz or is the
antenna's impeadance tuned to 50ohm or both?

The way the "Big Boys" do this is with an Impedance Bridge connected
to the Spectrum Analyzer, Tracking Generator, Antenna, and 50 Ohm
Termination Load. Then prune the antenna for the biggest NULL, at the
desired Operating Frequency. Been using this method for years on
MF/HF/VHF Marine Coast Station Antennas. sure takes the guesswork out
of the system.

--
Bruce in alaska
add path after fast to reply