hey richard:
as was said, theoretically, metal that close to the antenna will effect it's
radiation pattern etc. However, you've still got a whole lot of antenna up
in the clear. You must use ground radials with this particular antenna to
make it work at all though.
Also, I very strongly recommend not getting the 160 option for the
matching/tuning box at the bottom. Our club had one of these antennas, and
it worked really quite well with four 65 foot radials at the bottom, until
we added the 160M option...at which poit the antenna became almost useless
on all bands. It worked great from 80 through 6M without that 160 add
on...until, alas, it bent over in a wind storm and touched a power line and
fried everything including the radio attached to it lol.
We had it ground mounted on a piece of 1.5 inch pipe driven into the
ground...the bass was at about 1 foot or so off the ground.
Anyway, great antenna without the low band thing.
BTW, S9 antennas are on sale through cheapham.com and their 43 foot vertical
is on sale for a very good price...along with the radial plate and the other
various accessories.
you can score the 43 foot vertical with all hardware for under $200.
73
Colin, V A6BKX
--------------------------------------------------
From: "Richard B McDonald" <[log in to unmask]>
Sent: Saturday, June 28, 2014 7:15 AM
To: <[log in to unmask]>
Subject: A Technical Antenna Radiation Pattern Question Concerning Metal
within Walls
> Hi!
>
>
>
> For practical reasons (e.g., space issues, zoning restrictions, landlord
> concerns, etc.), I am thinking about putting up a MFJ 43' vertical 160 - 6
> meter antenna
> <http://www.mfjenterprises.com/Product.php?productid=MFJ-2990>
> . This question relates to how metal content within the walls of my house
> might affect the radiation pattern of this antenna. Basically, I am
> wondering if my walls will meaningfully interfere with transmit/receive
> operations of this antenna.
>
>
>
> The walls in my house contain about an inch thick layer of stucco which is
> meshed with chicken wire. This chicken wire is the kind with about 1.5"
> holes. On the inside of this is a layer of tarpaper. This tarpaper is
> secured with metal wire of about 18 gage running horizontally; with such a
> wire about every 8' from the bottom to the top of the wall. The rest of
> the
> wall is standard 2"X4" and plywood construction. The house was built in
> 1941. So, it is this chicken wire and tarpaper wire I am wondering about.
>
>
>
> This antenna would be ground mounted about 2' from the wall, and secured
> to
> the roof's eve overhang per MFJ's installation instruction in the manual.
> Also, there is a water heater within a metal enclosure that is about
> 3'WX3'DX7'H that is about 6' away from where this antenna would go. My
> house is single story; so about two-thirds of the height of this antenna
> would be above the rooftop.
>
>
>
> How much might the chicken wire and tarpaper wire mess-up my antenna?
> What
> about the water heater?
>
>
>
> 73 and happy Field Day!
>
>
>
> Richard KK6MRH
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