ah well, it wasn't my stuff lol.
our club station location has allot of stuff and things happen...we even had
the thing guyed in 2 spots to help prevent this.
We're supposed to be putting up a step IR vertical in place of the 43 foot
antenna, but who knows when that will actually happen.
73
Colin, V A6BKX
--------------------------------------------------
From: "Richard B McDonald" <[log in to unmask]>
Sent: Sunday, June 29, 2014 8:35 AM
To: <[log in to unmask]>
Subject: Re: A Technical Antenna Radiation Pattern Question Concerning Metal
within Walls
> Hi Colin!
>
> this is very helpful, practical information. Sorry your stuff blew-up
> when
> the antenna hit a power line : ) And, thanks for the heads-up on the
> antenna deal you mention!
>
> 73,
> Richard KK6MRH
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Colin McDonald
> Sent: Saturday, June 28, 2014 9:46 AM
> To: [log in to unmask]
> Subject: Re: A Technical Antenna Radiation Pattern Question Concerning
> Metal
> within Walls
>
> 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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