Our contest group operates from a mountain top at a commercial broadcast
facility. We suffered from lackluster 6M performance for our first couple of
years. Our 6M yagi was mounted on a mast attached to a one-story building at
the site. The antenna was about 1 wavelength above ground level. The light
went off for us when realizing that although the antenna was 1 w.l. AGL, it
was only about 0.3 w.l. above a significant amount of conductors (in the
form of feedlines and supporting structures within the building). We moved
the antenna such that it was greater than 1 w.l. above those conductors and
away from the building. This resulted in significantly improved performance
for us under non-Es propagation conditions. In short, remember to consider
all conducting surfaces (e.g., vehicle body) near the antenna.
Regards,
Stu
W3STU
Boonsboro, MD
EMConsulting
www.emcwizard.com
> -----Original Message-----
> From: vhfcontesting-bounces@contesting.com
> [mailto:vhfcontesting-bounces@contesting.com] On Behalf Of
> specrisk@aol.com
> Sent: Thursday, March 06, 2008 21:05
> To: vhfcontesting@contesting.com
> Subject: [VHFcontesting] 6 meter antenna heights
>
>
> In the past 3 VHF contests I have worked my 6 meter antenna
> (3 ele beam & ho loop) have been low. I was running 10 watts
> as SOP and my 6 meter performance was lackluster. Antenna
> height was about 15 ft. which worked okay? for the higher
> bands. I plan to operate as a rover in June and I can go to
> 30 Ft for 6 meters given the time to set it up. Power will be
> higher so it will be hard to make a direct comparison but as
> respects the June contest I? think putting an emphasis on 6
> meter antenna height is critical. What has amazed me is that
> my microwave antennas were? very low ( about 8 feet) but the
> height was less of a barrier.Having MW capability is great
> but if you are looking for score,? 6 meters is still the
> "magic band". George, W1JHR
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>
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