I call my idea an annex coupler.
I have a 240 foot dipole (120 ea side) fed with 400 ohm openline.
The open line goes to a 4:1 balun then rg 213 coax to the shack.
I use this on all bands 10 thru 80 meters coupling it thru a pi-network tuner.
The variable capacitors have plates 1/4 inch apart and the coil is variable
on a roller.
I get 1:1 swr on all bands. For 160M I bypass the tuner and get 6:1 swr.
I manged to make some contacts at this rate - my longest from MA to WY.
However, sigs are weak.
What I would like to do is feed the output of the tuner to another pi-network
just
for 160 operation. The theory is that the added capacitance and additional
coil would balance the line.
My experiments have not been fruitfull, I cannot even get the meters to move
when I do this.
I probably am not adding enough capacitance and/or coil.
Does anyone have any idea on how to approach this? How much capacitance and
coil to add.
My max that I have experimented with is 60 feet of #16 wound on a ceramic form
about 2/2 inches
in diameter and 6 inches long (overlapping) and one capacitor about the same
size as in the tuner.
Any ideas or links to 160 homebrew tuners would be appreciated.
Thank You
Joe
W1TW
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