Hmmm. Is this a good argument for motorized remote-controlled crankup
towers?
73, Dick, WC1M
-----Original Message-----
From: T A RUSSELL <n4kg@juno.com>
To: w7why@mail.coos.or.us <w7why@mail.coos.or.us>; TOWERTALK@CONTESTING.COM
<TOWERTALK@CONTESTING.COM>
To: <towertalk@contesting.com>
Date: Thursday, February 19, 1998 6:04 AM
Subject: Re: [TowerTalk] Antenna Peformance vs. Height and Elevation
>Antenna Peformance vs. Height and Elevation de N4KG
>
>>Hi Pete. Also, who is higher in elevation, etc. I have 3 elements on 20
>>at 35 feet and a friend has 4 at 60 feet and I'm consistantly beating
>>him out. But the location here is about 400 feet higher. 73
>>Tom W7WHY
>>
>
>Tom -
>
>I respectfully disagreee. Elevation alone has nothing to do with antenna
>performance. An antenna at 60 ft above a flat reflecting foreground at
>2000 ft elevation will have an identical pattern in the vertical plane as
>an
>identical antenna at 60 ft above a flat reflecting foreground at 500 ft
>elevation. TERRAIN and a sloping foreground on the other hand
>can have significant influence on antenna performance.
>
>Regarding antenna HEIGHT above a FLAT GROUND,
>HIGHER IS NOT ALWAYS BETTER. Often, higher angles produce
>stronger signals than lower ones, especially if the MUF is well above
>the operating frequency (this is particularly true on 20M) and the other
>station is also using a low antenna (as is most often the case for DX
>stations). If the ionosphere will support waveangles up to 20 or 30
>degrees and the distant station has a low antenna, he will be radiating
>more energy at the higher angles than the lower ones. A receiving
>antenna that matches the angle with the most energy (most likely
>one of a similar, usually lower, height, will be the best antenna to
>transmit back to the distant station. During mid-day when the
>MUF is high, my 40 ft TH7 often beats my higher monobanders
>to Europe and Africa. (AND, of course, all of my towers are at
>nearly the same elevation above sea level.)
>
>OLD MYTHS NEVER DIE .... HIGHER is NOT always BETTER
>
>de Tom N4KG
>
>
>
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