"engsol" wrote in message
...
On Fri, 28 May 2004 18:58:25 -0400, "Jack Painter"
wrote:


good stuff by Meindert snipped

:-)

Jack, I too wonder about the matching of (short) backstay HF antennas.
The thing that occurs to me is that trying to match the ATU to the antenna
isn't really the goal. The ATU *IS* the matching network. By feeding the
backstay with a coax, the excess capacitance (due to the coax) is just
another reactance the ATU must try to "tune out". Using coax is equivalent
to conncting shunt capacitors from there to ground.

Precisely

My opinion is that the lead, whatever it is, between the ATU and the
*real* antenna, becomes part of the antenna.

Indeed, it will radiate as much as the antenna does. Therefore it is best to
place the ATU immediately at the feed point of the backstay. The best
practical place would be directly below deck, underneath the backstay. Every
effort to keep the GTO15 as short as possible is best.

Meindert