I am frankly skeptical about this dire conclusion. For about 5 years I
used a multiband vertical on my garage roof, which is about 20/40 feet,
corrugated, semi-flat, and with only pretty tenuous (unmaintained)
screwed connections between sheets. Granted I was only running 100
watts (second radio in SO2R), but I heard no evidence of
cross-modulation. One thing I did that may have helped - in addition to
a direct ground to the sheet right under the base of the vertical, and
to a ground rod nearby, I laid out about 100 feet of wire from the
ground terminal so that it coupled to all the sheets of the roof.
73, Pete N4ZR
The World Contest Station Database, updated daily at www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at
reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000
On 8/11/2010 10:45 PM, hanslg@aol.com wrote:
>
> Yes, and you will have plenty of cross modulation due to the very many
> lousy connections between the different metal sheets. You have the same
> problems receiving, as you will have the same cross modulation from near and
> far located transmitters. Believe me, that's nothing you want to work with.
>
> If you have a metal roof with everything soldered together we may have a
> different animal but the way they are putting up metal roof by pressing the
> metals together, no.
>
> Hans - N2JFS
>
>
>
>
>
> -----Original Message-----
> From: Gary "Joe" Mayfield<gary_mayfield@hotmail.com>
> To: 'towertalk reflector'<towertalk@contesting.com>
> Sent: Wed, Aug 11, 2010 10:39 pm
> Subject: Re: [TowerTalk] Multi-Band Vertical Question
>
>
> Has anyone looked at installing one of a LARGE metal roof, and just using
>
> the roof as the ground plane?
>
>
>
> 73,
>
> Joe kk0sd
>
>
>
> -----Original Message-----
>
> From: towertalk-bounces@contesting.com
>
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim Brown
>
> Sent: Monday, August 09, 2010 10:08 AM
>
> To: towertalk reflector
>
> Subject: Re: [TowerTalk] Multi-Band Vertical Question
>
>
>
> On Mon, 9 Aug 2010 05:16:41 -0700 (PDT), GALE STEWARD wrote:
>
>
>
>
>> (3) Install the 14AVQ as an elevated ground plane with the base up 16-20
>>
> ft.
>
>
>> I would use 4 sloping radials for 20M which would double as guy wires. I'd
>>
>
>> then add two radials for 40M (these should also work for 15M) and two more
>>
>
>> for 10M.
>>
>
>
> While #1 is easier, I suspect that #3 will work better, because it gets the
>
> antenna up in the clear, away from other conductors that absorb power (like
>
> the wiring in your home, trees, etc.). When installing radials, I would
>
> study
>
> Rudy Severns' recent work on the topic. Google for N6LF to find his website.
>
>
>
>
>
> 73, Jim K9YC
>
>
>
>
>
>
>
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