I am going to tilt over my tower and check out my tribander before winter gets
too bad.
While it is down, I would like to put a sensing antenna near the driven element
to use as a pick up probe and with an rf voltmeter or field strength meter tune
for mjaximum radiation from the driven element.
I have seen pictures of towers with sensing antennas but I don't know anything
about it. I can't find anything on the internet about sensing antennas for ham
radio.
I have several tv antenna elements that are old but in mint condition. I plan
on mounting one horizontal on a boom at the top of the tower. The triband is
on a mast 5 feet above. Between the triband and the top of the tower is a
hinged swinging boom that holds the open wire feed of the driven element out
from the tower as the antenna is rotated. The boom at the top of the tower
holds a shunt fed wire that feeds the tower and a pulley for a delta loop. I
plan on cutting the tv element down to about 1 foot on each side of its
insulator - so it will be a 2 foot dipole. Does this sound like a ball park
lenght for the dipoloe?
I plan on feeding the sensing antenna with 300 ohm line down inside the tower
to a balun at the bottom of the tower. I will use an air balun from Orr's beam
antenna hand book p161. From the base of the tower to the operating position
will be coax. I built a field strength meter years ago but only used it over
time as an rf voltmeter.
Does this sound logical because I am not sure of what I am doing.
Any suggestions, ideas or thoughts would be greatly appreciated.
Thanks Paul WA5MUE
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