This interesting subject has so far has been educational !
But the original subject , I thought, would be discussed about shack
versus remote antenna tuners, which is a design project that I am
interested in.
My feeling is that most, if not all, antenna variable compensating
units (tuners), would be better served by installing them as close as
physical and mechanical possible to the antenna feed point, They
could then "Match" the antenna to 50R and allow VSWR free, and almost
lossless, coax to transport the signals to and from the antenna, Of
course this technique/concept works best when used with multi
band/frequency antennas,
At present I'm loath to find a QRO or better yet a QRO++, tuner
suitable for remote weather resistant mounting, other than the MFJ
998RT, and it's only single ended. I'd prefer one that also made the
conversion from balanced input to 50R output.
You may skoff, but I actually have an installed B&W style, MIL Spec,
folded dipole, that's 180' in overall length (using MILSpec SS
twisted multiple strand wire) and works quite well on especially 160
meters and up. This is in spite of the 800R power resistor in the
center of the far leg of the B&W dipole, I feed it with <100' of
7/8" Helix. This keeps the miss match VSWR loss, caused by the
coax, quite low even on the higher bands. The standing waves on the
incoming 7/8" coax are then tuned/matched by my HPA's auto-tuner. I
could actually mount such a tuner right at the feed point balun (it
probably needs to be replaced with a higher powered one), or I can
put the balun & tuner at the end of about a 20' run of ladder line,
near the bottom the tower, for easier access, BTW, this relative
sort tower that holds up the center of B&W. dipole, and a long boom
6M beam, is on top of a small 30' hill. This is at 5K' elevation,
with mostly a negative horizon. in the important directions.
Q.: In keeping with the true subject of this O.T., will this be an
advantage over, only using the auto tuner in my PW-1 PA ? And why
aren't there more remoteable, QRO, WX proof, auto tuners, on the market ?
Thanks for any comments or advice, 73, Chuck W7CS
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