Gem Quad
Sir Barry Duxbury
I have bought a 20/15/10 2 ele Gem and about to install it. Any
comments from users on the antenna would be appreciated
73 Barry(G4GAH)--
Barry Duxbury
bdux...@zetnet.co.uk
100031.2223@compuserve
G4GAH Oxford UK
Bduxbury_z...@gifl.com
From: bdux...@zetnet.co.uk (Sir Barry Duxbury)
Subject: Gem Quad
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Robert G. Strickland
bdux...@zetnet.co.uk (Sir Barry Duxbury) wrote:
>I have bought a 20/15/10 2 ele Gem and about to install it. Any
>comments from users on the antenna would be appreciated
>73 Barry(G4GAH)--
> Barry Duxbury
>bdux...@zetnet.co.uk
>100031.2223@compuserve
>G4GAH Oxford UK
Don't know about the Gem quad, but having used a 2el quad for three
years, I can assure you that you will be pleased with its performance.
Best antenna for the space/bucks you can put up. Have fun!
...Robert
Brett Coningham
>bdux...@zetnet.co.uk (Sir Barry Duxbury) wrote:
>>I have bought a 20/15/10 2 ele Gem and about to install it. Any
>>comments from users on the antenna would be appreciated
>>73 Barry(G4GAH)--
>> Barry Duxbury
>>bdux...@zetnet.co.uk
>>100031.2223@compuserve
>>G4GAH Oxford UK
I used to have a two-element Gem Quad, which lasted for nine years
until a 105mph wind blast finally broke one of the very strong arms.
Overall, I was very happy with this antenna, and during a period when
I was a DX-er, was able to work 310 countries with it. In comparisons
with a neighbor who ran a 52-ft five-element 20m monobander, at 70ft,
my quad at 55ft usually performed just about as well in the DX
pileups. I know there were times when I could hear weak signals
that he couldn't, and vice-versa.
I had to make a few modifications over the years, though, as follows.
(1) After a couple of years of our usual high wind seasons, the wire
stretched so much that the tuning of the antenna was out of
whack. Another ham buddy and I went in together and bought
a bunch of 1/16th-inch Copperweld wire, and I re-strung the
antenna with it. It never stretched out of spec again.
(2) The Nylon ties that originally held the wires to the spreaders all
disintegrated in the Sun, and I replaced these with 14-guage
copper wire, strung through the holes in the spreaders, and
wrapped around the antenna wire on both sides of the spreader.
This held the wires with no further trouble.
(3) The original Balun idea worked pretty well, but after replacing
the wire with Copperweld wire, I could never get it tuned again
using the original Balun. I ended up using 1/4-wave matching
sections of 75-ohm coax for each band, which converted the
nearly 100-ohm impedance down to about 50 ohms. SWR
was less than 1.5:1 across all three bands, and tuning the
Front-to-back became very easy with the shorting stubs.
After the quad broke, I tried a Hygain 204BA monobander, but
never was happy with it. Probably it wasn't high enough at 55ft.
After the DX-bands became such a zoo of bad manners and
list-takers, I gave up DX-ing and didn't replace the Gem quad,
but if I ever get interested in HF again, I'd sure consider having
another.
One thing I noticed was that it would pick up static electricity
like you wouldn't believe. Whenever the wind would blow, I'd
disconnect if from the radio, and you could see sparks jump across the
inner and outer parts of the coax connector!
I think you will like the antenna, but be prepared to spend some
time to get it tuned properly (a characteristic of all quads).
Tuning the F-B is easier if you have a couple of helpers, one
down in the shack to rotate the antenna, one across town to
give you a test signal, and yourself up at the antenna to
adjust the shorting stubs.
73
Brett
docn...@bigpond.net.au
> I have bought a 20/15/10 2 ele Gem and about to install it. Any
> comments from users on the antenna would be appreciated
> 73 Barry(G4GAH)--
> Barry Duxbury
> bdux...@zetnet.co.uk
> 100031.2223@compuserve
> G4GAH Oxford UK
Dr Charley Nadin Anaes
Bunbury Western Australia vk6acf
Allodoxaphobia
> On Monday, July 1, 1996 3:00:00 PM UTC+8, Sir Barry Duxbury wrote:
>> I have bought a 20/15/10 2 ele Gem and about to install it. Any
>> comments from users on the antenna would be appreciated