[Elecraft] T.G.M. Hybrid Quad

Tue Apr 22 17:06:01 2003

I used the mq-2 for several years and coupled the rig to it via an mfj versa
tuner. The antenna worked better than my g5rv, vertical, or other non-beam
type antennas. It had gain and some fb. It made a difference in working them
or not at times.

        Reggie K6XR

-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of Thomas Miccolis
Sent: Tuesday, April 22, 2003 12:52 PM
To: [email protected]
Subject: Re: [Elecraft] T.G.M. Hybrid Quad

Date: Mon, 21 Apr 2003 15:31:07 -1000

Hello,

I was wondering if anyone has used the T.G.M MQ-1 or MQ-2 with their K2 and
if so, how well the antenna tuner performed with it. I was considering the
MQ-2 since it has mostly 5-6 dBd gain across 6 bands and its small footprint
is just what I need.

Don't have one but don't be misled into the trap of gain versus bandwidth
versus "radiation resistance".  Nothing else matters if your antenna's
radiation resistance is poor (low).  That's where the "dummy load" analogy
comes from.
It appears to be a relatively narrow bandwidth antenna. I kind of understand
that performance is not directly related to low SWR (i.e. dummy load) but I
would be interested in opinions of how gain would be affected as the antenna
bandwidth is extended with the KAT100.

Regardless of which antenna you select the "performance" is related to
several components but mostly by "Radiation Resistance" (sometimes
incorrectly coorelated to "efficiency").  Radiation resistance has to do
with antenna modeling but the basic thing is that most of those "numbers"
that you see in antenna ads are pretty much meaningless UNLESS your antenna
installation situation closely matches the manufacturer's antenna test range
(usually not).  So to answer your question more accurately the "bandwidth
and gain" have more to do with "how high (above everything else including
your roof) and on what (non-metal?)" you will be mounting it on.  You can
"stuff RF energy into it" via a KAT100 (maybe) but how effectively it
radiates depends on how it is installed, how it is fed, and how it was
adjusted/tuned.  You also need to look at the plots of that 5-6 dB of gain
(compared to an isopole or a dipole?) to determine what it may actually do
for you even in an "ideal", optimized !
 installation.
So basically on any "compact" antenna design you can pretty much write off
at least half of those "numbers" due to practical limitations of an
installation versus an antenna test range facility (is 2.5-3dB really all
that impressive now?).  Then your actual numbers go down from there (more
like 1-2 dB).  But hey, if due to all kind of constraints it is all you can
put up that will STAY up, it beats nothing (probably at a hefty price
though).  Be aware that this type of antenna (the old Erie, PA ones) need to
be tuned properly and do not handle any abuse very well.
All things considered they work "OK"but I often wonder, for all their grief,
if a suitable trap-dipole, G5RV, or open-wire line fed dipole, up at least
as high or higher wouldn't do a much better job for far cheaper a price.

Tom M., WA3UZI

&nbsp;

------------------------------------------
Help STOP SPAM with
------------------------------------------
the new MSN 8
------------------------------------------
 and get 2 months FREE*
------------------------------------------

--- StripMime Report -- processed MIME parts ---
text/html (html body -- converted)
The reason this message is shown is because the post was in HTML
or had an attachment.  Attachments are not allowed.  To learn how
to post in Plain-Text go to: http://www.expita.com/nomime.html  ---
_______________________________________________
Elecraft mailing list: [email protected]
You must be a list member to post to the list.
Postings must be plain text (no HTML or attachments).
See: http://mailman.qth.net/mailman/listinfo/elecraft
Elecraft Web Page: http://www.elecraft.com