Rob,
Back in the late 70's there were about a half dozen two-element Gem quads in
use here in the Albany, NY area, mine included. The first antenna put up by
an old-timer followed the directions exactly and worked fine except that the
smallish-gauge solid copper wire had a tendency to break after flexing for a
year or two. We were constantly fixing it. For mine, I chucked the
instructions, bought 14 gauge 7 strand copperweld (I think the same as your
copper clad) and bought the Bill Orr Quad Antenna book. In that book there
is a section on mono-band quads--since a spider quad is really three mono
banders, not a tri-band quad (as with all the loops on the same vertical
plane). We also chucked the matching stubs on the reflectors in favor of
closed loop reflectors which are structurally much better and work just as
well because a quad is a low Q antenna and the dimensions are not too
critical. The quad book for monobanders said to use 1005 divided by
frequency for the reflector and 995 divided by frequency for the driven
element. I tied 10 and 15 meters together at the middle and fed 20
separately with a quarter wave match of 72 ohm coax. You can use three feeds
if you want, but I thought it unnecessary. Place the wires through the
wire-guides loosely around the spider and then move them out all around as
far as necessary to get the wires almost taut. Also use some small string
and support the coax back up to the spider so all the weight is not on the
loops. Thereafter all the quads were built per my experience. The Gem Quad
is an excellent performer and you will be happy with it. Won't make any
claims about how "great" it is based on DXCC totals, but the old timer had
No. 1 DXCC with the quad at 40 feet in a "hole" in the center of Albany. Of
course back then there were no packet/packet pile-ups and you had to find
the dx yourself. In case your wondering, I took down my quad to replace it
with a stack of homebrew 4-element wide-spaced yagis. Good luck. 73 Saul
K2XA
----- Original Message -----
From: "Van K7VS" <wa7fab@cdsnet.net>
To: "Rob Frohne" <frohro@wallawalla.edu>; "towertalk"
<towertalk@contesting.com>
Sent: Thursday, February 14, 2008 2:55 AM
Subject: Re: [TowerTalk] Copper Clad or Hard Drawn Wire for Quad?
> Rob: I am currently running a 3 el gem quad and have a four element gem
> quad hanging in the garage! I can tell you that what they recommend is to
> restring with the same wire as comes with the unit. It is enamel number
> 18
> or 20 soft drawn copper wire found at any motor rewinding shop in your
> town.
> Anything other than the size they originally used will change the tuning
> significantly as the velocity factor will be different. Also, if you can,
> use 1/4 wave matching stubs on all three bands and performance will
> improve
> and you will have a much lower swr than if you tie all three driven
> elements
> to a single feedline as they show in the manual. Good luck and think you
> will find it a top performer. Van, K7VS 337 current countries worked and
> confirmed with only FR/G still needed and all with the Gem Quad!!
>
> ----- Original Message -----
> From: "Rob Frohne" <frohro@wallawalla.edu>
> To: "towertalk" <towertalk@contesting.com>
> Sent: Wednesday, February 13, 2008 10:09 PM
> Subject: [TowerTalk] Copper Clad or Hard Drawn Wire for Quad?
>
>
>> Hi,
>>
>> I was given a broken Gem Quad, which I am attempting to splint together,
>> and it needs all new wires. I'm wondering whether to use #14, 7 strand
>> copper clad steel or #14, 7 strand hard drawn copper wire which may be
>> more flexible. I'm also a little worried about galvanic action on the
>> copper clad steel. But the steel seems like it would be stronger. What
>> are the opinions here?
>>
>> Thanks & 73,
>>
>> Rob, KL7NA
>>
>> _______________________________________________
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>
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