Anyone have experience with GAP Antennas? On paper they look almost too good
to be true, but I know that word of mouth can be more informative. All
comments welcomed.

west
AF4GC

west wrote:
Anyone have experience with GAP Antennas? On paper they look almost too good
to be true, but I know that word of mouth can be more informative. All
comments welcomed.

"If it sounds too good to be true it probably isn't . . "

Here's a load of "opinions" on the Gap line:

http://www.eham.net/reviews/products/13

west
AF4GC

w3rv

Have you considered the Hustler 4 or 5 or 6 BTV line?
I have added 12M and 17M to my 5-BTV and now have what I call a Hustler
7-BTV (10,12,15,17,20,40 and 80M)
Cost me $10 and about 2 hours time start to finish...

Details, photos, parts list etc here
1. http://www.ad5th.com/5-BTV-WARC.html
--

Charlie


"west" wrote in message
. ..
Anyone have experience with GAP Antennas? On paper they look almost too
good
to be true, but I know that word of mouth can be more informative. All
comments welcomed.

west
AF4GC

I bought a Gap Titan a few years ago because it is a vertical dipole.
It has been a satisfactory antenna. It is noticably quieter than a
1/4 vertical and there's no need for the ground screen neccessary to
make a 1/4 wave vertical work.

I have it mounted in my back yard on a pipe driven into the ground. It
is about three feet off the ground.

It's pretty much worthless on 75M and marginal on 40M. On 20M and up
it does OK. Depending on the time of year, it performs better than
the W5GI I have at 40 ft. I prefer it to any of the 1/4 wave
verticals I have used.

Steve, WA4ITA

On Sat, 17 Dec 2005 05:05:43 GMT, "west"
wrote:

Anyone have experience with GAP Antennas? On paper they look almost too good
to be true, but I know that word of mouth can be more informative. All
comments welcomed.

west
AF4GC

It is noticably quieter than a
1/4 vertical ............


Note...A red flag should always go up when noise is reduced
vs another antenna of the same basic type. :/
Worthless on 75m? If this is late at night when a vertical
"should " do well, I'd be concerned.
Myself, I've never been much of a fan of gap verticals.
But...I'll leave it at that.. I like regular ole full size verticals
in general. Only my mobile uses a stunted vertical.. :/
BTW..If the vertical is not a complete antenna, as in halfwave,
it needs a groundscreen no matter where on the radiator the
antenna is fed, if it's ground mounted. Even a half wave is
improved when ground mounted. Note that most BC stations
that run 1/2 waves, use 1/2 wave radial screens under them.
MK

I picked up a used one last sprng, set it up about 3 ft off the ground in
the back yard...and took it back down within a couple of weeks.
Signals were way down compared to my 450 ohm ladder line fed 80 meter
doublet on all bands.
I remade the Titian into a 40 ft vertical dipole that I use on 40 thru 10
meters, fed with twin lead, and much better results.
"west" wrote in message
. ..
Anyone have experience with GAP Antennas? On paper they look almost too
good
to be true, but I know that word of mouth can be more informative. All
comments welcomed.

west
AF4GC

Denton wrote:
I picked up a used one last sprng, set it up about 3 ft off the ground in
the back yard...and took it back down within a couple of weeks.
Signals were way down compared to my 450 ohm ladder line fed 80 meter
doublet on all bands.

I had the same experience with a 1/4WL 40m vertical. Now I wish
I had run some A/B transmitting tests as well as the A/B
receiving tests which the vertical flunked mainly due to an
extremely high noise level. I'm thinking about putting the
vertical back up as a 1/4WL 30m vertical fed at the base with
an SGC-230 that I already have. Such an antenna should work
pretty well on 40m-10m, at least for transmitting.
--
73, Cecil http://www.qsl.net/w5dxp

Hi Cecil....let us know if you do that. When I redid the back yard lawn, I
installed an extensive buried radial system for such experimentation. I have
all the aluminum tubing left over from the Titian's tuning stubbs to turn my
40 ft vertical dipole into something wth some capacity hats...to get it to
work on 80 thru 20 meters, if I desire.
"Cecil Moore" wrote in message
. net...
Denton wrote:
I picked up a used one last sprng, set it up about 3 ft off the ground in
the back yard...and took it back down within a couple of weeks.
Signals were way down compared to my 450 ohm ladder line fed 80 meter
doublet on all bands.

I had the same experience with a 1/4WL 40m vertical. Now I wish
I had run some A/B transmitting tests as well as the A/B
receiving tests which the vertical flunked mainly due to an
extremely high noise level. I'm thinking about putting the
vertical back up as a 1/4WL 30m vertical fed at the base with
an SGC-230 that I already have. Such an antenna should work
pretty well on 40m-10m, at least for transmitting.
--
73, Cecil http://www.qsl.net/w5dxp

Cecil Moore wrote:
Denton wrote:
I picked up a used one last sprng, set it up about 3 ft off the ground in
the back yard...and took it back down within a couple of weeks.
Signals were way down compared to my 450 ohm ladder line fed 80 meter
doublet on all bands.

I had the same experience with a 1/4WL 40m vertical. Now I wish
I had run some A/B transmitting tests as well as the A/B
receiving tests

I thought you did that with N2EY . . ?

which the vertical flunked mainly due to an
extremely high noise level.

I did some of that sort of A/B testing between an elevated 1/4 wave 40M
GP and an 80/75/40M 130 foot end-fed inverted L a number of years ago
and the GP did not fare well at all. As it happened there wasn't much
of an electrical noise problem in the neighborhood then so QRN one way
or the other was not a term in this specific equation.

The vertcal leg of the inverted L was spaced about 20 feet from the
tower and was base-fed by a remotely controlled L/C tuner out in the
back yard, a USN surplus gun director selsyn motor cranked a big rotary
inductor which allowed me to QSY from 40 to 80/ 75. But the process ate
a minute or two to do which was a pain in the tush during the DX
contests I was into. Instantaneous band changing in that game matters.

The apex of the L was around 60 feet AGL. The 70 foot "horizontal" run
sloped down from the apex to about 35 feet AGL. The L worked quite well
on both bands, I could snipe JAs at will with just an SB-200 on either
band from here on the east coast when band condx were decent.

I decided that I had to put up some kind of 40M antenna so that I could
quickly QSY from 80/75 to 40 by simply flipping an antenna selector
switch which would get me away from the increasingly annoying "twist
the selsyn 30 turns" routine when band swapping.

So I built a textbook-classic 40M 1/4 wave GP which had a
self-supporting 35 foot +/- radiator. The base was at 35 feet AGL,
there were four downward-sloping wire radials. The whole thing perched
atop the roof of the abode. SWR over the entire band was essentally
unity.

Turned out to be a complete waste of time, money and effort. For
whatever reason or reasons there wasn't much difference in received
signal strength levels beteen the two antennas when I was listening to
long-haul DX like JAs and VK/ZLs on my end. But when I called them more
times than not they did not come back to me. I spent a couple intense
very early morings A/B swapping between the L tuned for 40M and the GP
QSOing the DX. In 90% of the cases they "heard me much better" when I
was using the L than they did when I used the GP. I took the GP down
and good riddance.

I'll leave the theoretical howcums of my experince to those of you who
are deep into the physics of electromagnetics. For my part another 1/4
wave HF GP just ain't gonna happen here again elevated with radials or
ground mounted with gazzilion radials.

.. . . half-wave verticals being a whole different ballgame . .

I'm thinking about putting the
vertical back up as a 1/4WL 30m vertical fed at the base with
an SGC-230 that I already have. Such an antenna should work
pretty well on 40m-10m, at least for transmitting.

Go for it and post your results.

--
73, Cecil http://www.qsl.net/w5dxp

w3rv

I'll leave the theoretical howcums of my experince to those of you who
are deep into the physics of electromagnetics. For my part another 1/4
wave HF GP just ain't gonna happen here again elevated with radials or
ground mounted with gazzilion radials. ..........................


Kinda weird. The one I used here worked great. And almost
identical specs. Mine was full size at 36 ft with 4 sloping radials.
The only thing I can think of to explain it , would be ground quality.
Evidentally, my ground quality must be pretty good compared to
many areas of the country. I know it's a good bit better than Cecils,
judging by the conductivity maps. If your's didn't work up to par,
I'd almost have to blame it on the radial system. I think you probably
needed a few more to equal what I had here. In fact, going by the
numbers, for a 1/4 wave at a 1/4 wave high, you really need 8 radials
to equal 120 on the ground. I judged my 4 radials as being equal to
about 60 radials for a ground mount. But...My conductivity rating in
this area is bordering on the "30" range being I'm not too far from the

coast. I know for sure Cecil would need more radials than mine for
the same performance, as his was half the height and his ground
rating is lower. .
My hunch is if you had 8 radials on the GP, it probably would have
done better.
My GP totally smoked the ground mount I had that used 32 radials.
No comparison at all. I've never tried 1/2 waves on the low bands,
except for extended inv-L's...I have run them 20m up though.
Work well there.
MK