Joe said
"You want to get on 160, but do not have an actual 160 antenna. So you
connect the largest antenna ya have, usually a 80 meter dipole, but you
just push the connector in just so only the center pin is touching, and
load the whole thing up like a top capacity hat, vertical, or end fed
long wire. Hey it works. "
Back many years ago I did the same thing. Well, I knew better but I had
this flash of stupidity overcome me and I wanted to use it while it was
fresh. I blew out all the horizontal drivers in the big projection TV set.
Jerry, K4SAV
On 12/17/2018 8:31 AM, Joe wrote:
OK, as users of this band, we all have probably done this at least
once in your radio lifetime.
You want to get on 160, but do not have an actual 160 antenna. So you
connect the largest antenna ya have, usually a 80 meter dipole, but
you just push the connector in just so only the center pin is
touching, and load the whole thing up like a top capacity hat,
vertical, or end fed long wire. Hey it works.
I'm thinking of doing something similar, because a full sized 1/4 wave
elevated vertical for 40 meters, works as well as a cannenna does when
trying to use it on 160.
But I never thought of what might be the best way to do this. The
antenna as stated is a full sized 1/4 wave elevated Vertical, The
base of the vertical is 10 feet above the ground with sloping radials
that act as guy wires also to hold the base in place.
At the base of the antenna right at the feedpoint, is a large multi
turn coax choke. ( Ya know the so many turns on a PVC pipe thing )
The feedline is then ran through the air for about 60 feet to the eve
of the house where it runs along the eve of the house on 2 sides and
finally into the shack. Total length is about 100 feet.
Now I am trying to decide without actually trying to make up
connectors or whatever, what might be the best way to use this on 160.
1- As described above just the center pin, touching. I guess with the
braid floating the braid gets capacitivly coupled to the power and
does the radiating and receiving. YES? NO?
BUT I can see the RF actually also going and using the existing
vertical because of the touching center pin. BUT, the braid signal,
I'm assuming the RF is not getting past the Coax coil and using the
radials.
2- Apply power to only the braid? similiar to #1 but backwards. again
no power to the radials probably?, and only cap coupled to the vertical.
3- short the center and shield together and run it that way.
Anyone have any thoughts of the best configuration any thoughts?
Or how would a end fed random wire like 1/4 wave long about 10 feet up
work better?
Joe WB9SBD
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