[Antennas] Radial Wires VS a wire or screen mesh
Gary K9GS
garyk9gs at wi.rr.com
Sun Nov 15 11:25:08 EST 2009
I have an 80M ground mounted vertical (modified HF2V) with ~25 X 65 foot
long radials. Two weekends ago I put down 100 feet of 2 foot wide chicken
wire ground screen. The chicken wire is laid out roughly in the shape of an
X...not a +...if that makes sense. The radials are insulated wire and the
ground screen is simply laid on top of the radials with no effort to bond
them together except at the base of the antenna.
I'm curious how K1TTT bonded the mesh and connected them to the feedline?
What I did was purchase 4 pcs of galvanized steel perforated stock. This
stuff is available at Home Depot and is ~2" wide and perforated with a 3/8"
diameter hole about every inch. I cut each 4 foot piece in half...making
two two foot pieces which fits nicely across the two foot wide chicken wire.
I folded the ends of the chicken wire over 4 times...about 2" wide and then
sandwiched this between the two pieces of perforated stock. About every 3
or 4 holes I use a 1/4-20 bolt that I torque down very tightly. Prior to
bolting the perforated stock together I liberally brushed the perforated
stock/chicken wire with penetrox/conductive grease.....quite a mess to
handle :))
At the base of my vertical I have one of the Lance Johnson radial plates.
In addition to terminating all of my radials, I then used two of the
perforations per "chicken wire radial" to bolt directly to the radial
plate...they use 1/4-20 bolts already.
The chicken wire was also purchased at Home Depot and comes pre-cut in 25
foot rolls. It was pretty cheap and I figure if I can get a season or two
before replacing it will be worth it. I'll probably roll the chicken wire
up in the spring.
I have noticed a substantial improvement on 80M and 40M in what I am able to
work. The tuning did change slightly...that's the next thing I have to
adjust before it snows ;)
73,
Gary K9GS
++++++++++++++++++++++++++++++++++++++++++++++++
K9GS
Gary Schwartz email: k9gs (at) arrl.net
Check out K9NS on the web: http://www.k9ns.com
Society of Midwest Contesters (SMC) http://www.w9smc.com/
GMDXA http://www.eng.mu.edu/gmdxa/
++++++++++++++++++++++++++++++++++++++++++++++++
----- Original Message -----
From: "K1TTT" <K1TTT at ARRL.NET>
To: <antennas at mailman.qth.net>
Sent: Sunday, November 15, 2009 5:47 AM
Subject: Re: [Antennas] Radial Wires VS a wire or screen mesh
>I use 2"x4" mesh fence wire under my raised radials on my 80m 4-square.
> When I first did the installation I did measurements as I added radials to
> the first vertical and then as I rolled out 150'x4' in a cross pattern
> under
> the vertical. There was much more change going from 4 to 8 raised radials
> than there was in adding the screen, but it did seem to help a bit. The
> wire in that fencing is much heavier than chicken wire and I have gotten 5
> or 6 years out of it so far. I roll it up in the spring so I can cut
> grass/weed under it and roll it out again before the fall contests and
> snow
> start flying.
>
>
> David Robbins K1TTT
> e-mail: mailto:k1ttt at arrl.net
> web: http://www.k1ttt.net
> AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
>
>
>> -----Original Message-----
>> From: K2RS [mailto:K2RSonline at comcast.net]
>> Sent: Sunday, November 15, 2009 02:21
>> Cc: antennas at mailman.qth.net
>> Subject: Re: [Antennas] Radial Wires VS a wire or screen mesh
>>
>> The contest station with the chicken-wire ground system for its 160
>> antennas is always near the top of the multi-multi category in major DX
>> contests and manages to rack up lots of Qs on 160 meters. So, while the
>> chicken wire might not be optimal, it works in the real world and, in
>> the end, that's all that really counts.
>>
>> Jack K2RS
>>
>> Terry Conboy wrote:
>> > This is probably fine as far as it goes. The problem is that with only
>> > 4 rolls of chicken wire, there is still a lot of soil between the
>> > conductive mesh. The idea of using a large number of wire radials is
>> > to
>> > provide a path for the RF displacement current back to the base of the
>> > antenna that only involves a very short distance for current flowing in
>> > the poorly conductive soil until it reaches a good conductor.
>> >
>> ______________________________________________________________
>> Antennas mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/antennas
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Antennas at mailman.qth.net
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>
>
> ______________________________________________________________
> Antennas mailing list
> Home: http://mailman.qth.net/mailman/listinfo/antennas
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Antennas at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
More information about the Antennas
mailing list