|To:||Larry Phipps <email@example.com>, <firstname.lastname@example.org>|
|Subject:||Re: [TowerTalk] Actual LP Performance vs Tribanders|
|From:||Pete Smith <email@example.com>|
|Date:||Mon, 28 Jun 2004 07:02:02 -0400|
At 02:08 AM 6/28/2004, Larry Phipps wrote:
Jim, I'm not that familiar with the beacons, but since your post I did a little research. There are a couple of major problems.
Frankly, I think these are show-stoppers, as Larry says. Another issue is that S-meters can be quite non-linear -- for example, my Mark 5 is (very roughly) 2 dB per S Unit below S-9, and then fairly abruptly transitions to ~6 dB per S-Unit.
That's why I use the trick, told to me by W3LPL, of varying the transmitter power to maintain a reference S-meter level, rather than counting S units at constant power. In the test of my 40m beam that I ran last week, power required to maintain the reference level varied from 20 watts to 1400 as I rotated the antenna. Of course, the accuracy of the power meter is still an unknown, unless you know how it is calibrated, but a 5-10 percent error in power is still pretty small when converted to dB.
I used the phone to coordinate with a neighboring ham, but even if you interspersed phone transmissions and steady carriers to do it over sky-wave distances, it wouldn't take very long to plot an antenna pattern this way.
73, Pete N4ZR
The World HF Contest Station Database
was updated on June 5, 2004
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See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.
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