Roger, you lucky dog! Sure wish the other 99% of us hams had the money and
space to have such an antenna farm. But since we don't and are forced to
live with antenna restrictions or limitations, what advice do you have for
us? Many of us are lucky to obtain permission to put up one inconspicuous
antenna, preferable hidden, so what antenna should we choose, feed with 50
ohm coax and work all bands without the need for a matchbox?
I doubt that anyone of us disagrees with you, in theory, but it's simply not
practical for most people. The reality for most of us is wire and matchbox.
Under these circumstances, how can we optimize our setup? Someone suggested
to use a 238 instead of a T-filter. I think that was good solid advice,
though a link-coupled matchbox is better for running a doublet (random
length) with openwire.
Two of my neighbors also use an inverted L on 160m (slightly longer than 1/4
lambda. They tune it with a variable C at the base, remotely. I planned
that too, but got lazy and just trimmed the antenna to resonance, band
middle. I have about 100 ft. of coax and tune in the shack with a 238. I
can hear and work everything that the other two can. I don't see the point
in the extra effort it takes to implement the remote tuning.
73
Rick
DJ0IP
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Roger Borowski
Sent: Wednesday, January 18, 2006 4:39 PM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] What makes the 238 good or any other tuner good?
After more than 45 years of continual hamming on all bands and modes, I can
honestly say that I never have used an antenna tuner and never found any
system that will outperform a resonant antenna fed with coaxial cable, which
I've always used since the early 60's. If the antenna isn't resonant on the
desired frequency of operation, many people think an antenna tuner is the
fix. While an antenna tuner will allow you to use most anything metallic as
a radiator of RF, the most efficient power transfer is to a 50 ohm resonant
load via 50 ohm coaxial feedline. In all cases where an antenna tuner is
used with a coaxial fed antenna, all it does is further complicate a system
with an added piece of equipment that only fools the transmitter into seeing
the match it is looking for, while creating losses in itself and further
losses in the coaxial feedline due to the mismatch that still remains
between the antenna tuner and the antenna. Fortunately I've never been
forced to use anything other than resonant antennas fed with good quality 50
ohm coaxial cable. If you're bound and determined to use open wire feeders
to one of the many non-resonant antenna designs of yesteryear, that would
require an antenna tuner. Why anyone who understands antennas would want to
do that 50-60 years after coaxial cable became common place is beyond my
comprehension. It's an easy chore to adjust antenna lengths for resonance
and where available space doesn't permit, it's also easy to use loading
coils or linear loading configurations on the antenna. If you haven't a clue
as to what I'm saying, pick up a book on antennas, such as the ARRL Antenna
Book and read the entire section on the theory of antennas. As a Ham, you
really need to know this. An antenna tuner is a band aid approach that
allows one to use an inefficient antenna, whatever it may actually be, with
some degree of success. You see 1:1 SWR on the tuner meter and you and your
rig are happy, but in actuality, put another SWR meter after the antenna
tuner and you'll see the real mismatch, why you are generating RFI, and
experiencing far less performance, both transmitting and receiving, than you
could be.
73, -=Rog-K9RB=-
FCC First Class Commercial License first attained in 1967, Ham Radio license
first attained 1961.
A-1 Operator Club, ARRL Life Member, DXCC #1 Honor Roll (350) Mixed, Phone,
CW (since '92) and presently need 11 more on RTTY for H.R. Need (4) more
zones on 160M. for all (9) HF band "Worked All Zones". At present 160 Meter
DXCC - 211 + 36 zones. Former member NIDXA No.Ill.DX Assn., 9th area
incoming QSL bureau sorter for many years, Charter Member Metro DX Club,
Life member / former Trustee W9AA Hamfesters ARC., CP-40 in 1963 at 14 years
of age, former ARRL OO, & NCS, active 160M through V.H.F. / U.H.F. for 45
years. 1st place CQWPX-CW 15M in 1981. 1st place CQWW-CW 40M in both 1980 &
1988. (Ancient history now!) Also KG4RB -GTMO Cuba, Bio and photos available
at www.qrz.com Reply direct to; K9RB@arrl.net
----- Original Message -----
From: "Richard Williams" <richardw@mho.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Wednesday, January 18, 2006 5:43 PM
Subject: Re: [TenTec] What makes the 238 good or any other tuner good?
Rich,
Quite a number of answers I see on the board. My personal opinion is the
best tuner out there is the XMatch tuner manufactured by Paul Schrader
(N4XM). This is pretty well backed up by the ARRL when they did a review
of this one and three others back in Mar of 97. You can read it by signing
on to the ARRL home page and search for XMatch tuner.
I don't think anything comes even close to it specs when operating on 160
Mtrs. I believe he still makes them as I see his ads in EST..
Maybe someone else out there has the Match and will put there "two cents"
worth in.
Dick KHZ
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