John Ferrell wrote in
:

On Mon, 04 Dec 2006 09:18:47 -0500, chuck wrote:

John Ferrell wrote:
I am considering purchasing a remote auto tuner for my continuing

As others have noted, the auto tuners will have no trouble matching a
33 foot vertical on either 80 or 160 meters, even over sea water.

Using one at the antenna may reduce losses in your coax since the swr
will always be low.

The auto tuners will introduce their own losses, as will any antenna
tuners, although with shorter antennas the losses may be greater. QST
had an article in which auto tuner losses and matching ranges were
measured and I think compared with conventional tuners. If I recall,
the results were less unfavorable toward auto tuners than I had
expected.

To reduce auto tuner matching losses to insignificant levels, you
might consider adding some lumped inductance at the base of your
vertical (or even better, part way up as in center-loading). You can
add a capacitance hat as well. If you cause the 33 foot antenna to
appear resonant at either 80 or 160, you will see reduced auto tuner
matching losses on both bands. Just a rough approximation to the
required number of turns ought to work. You're only trying to provide
enough external loading to reduce the tuner's losses. Resonance really
doesn't matter much. If you do this, you should be able to enjoy the
ease of QSY without a serious loss penalty and without a need to
switch taps or retune manually.

Of course your 33 foot vertical resonant at 80 or 160 meters may not
perform well at 40 meters and above, or worse, may not provide an
impedance your tuner can handle at those frequencies.

Chuck, NT3G

I have updated the 28 foot vertical web page for those who may be
interested in my experience. I is at
http://www.dixienc.us/28FtVert/SGC237.htm

I am very pleased with the results using the tuner but it has only
been a few days, I am still in the "honey moon" phase. I outline the
considerations for me and a larger vertical at the web site.
John Ferrell W8CCW

John, re the lighting protection issue with the tuner.

I don't need or want to operate when there is a high risk of lightning,
so I disconnect the tuner. The last picture in this article shows how
the tuner is mounted and the simplicity of an effective isolating
switch. In the event of lightning strike, the inverted L wire will
probably side flash to the support mast where it is much closer. One
could of course build a sturdy arrestor near the tuner if you don't have
such an alternative.

http://www.vk1od.net/InvertedL/InvertedL.htm

Pleased it is all working well for you.

Owen

On Tue, 02 Jan 2007 02:07:57 GMT, Owen Duffy wrote:


I have updated the 28 foot vertical web page for those who may be
interested in my experience. I is at
http://www.dixienc.us/28FtVert/SGC237.htm

I am very pleased with the results using the tuner but it has only
been a few days, I am still in the "honey moon" phase. I outline the
considerations for me and a larger vertical at the web site.
John Ferrell W8CCW

John, re the lighting protection issue with the tuner.

I don't need or want to operate when there is a high risk of lightning,
so I disconnect the tuner. The last picture in this article shows how
the tuner is mounted and the simplicity of an effective isolating
switch. In the event of lightning strike, the inverted L wire will
probably side flash to the support mast where it is much closer. One
could of course build a sturdy arrestor near the tuner if you don't have
such an alternative.

http://www.vk1od.net/InvertedL/InvertedL.htm

Pleased it is all working well for you.

Owen


After reading your web pages I have begun to imitate your set up. I
will be using a 44 foot wire radiator. It will (is) angling down to
one of the ground rods. That will permit the tuner to be installed
inside the house. This set up is physically much simpler for me. The
tower is a crank-up/tilt over arrangement with no guys so the actual
rigging must allow for a lot of movement.

John Ferrell W8CCW