[VHFcontesting] More 6 meter antenna heights and rambling
fredlass at global2000.net
Tue Jul 31 21:26:31 EDT 2001
Answer to Dave, K8CC;
20/40 also seemed low for six meters to me the first time that I heard
about it. However, in terms of wavelengths that equates to 70/140 on 20
meters! (140/280 on 40 meters) Those heights were magic for the W1VD
effort a number of years ago. Of course Clarke Greene, K1JX, as an
operator helped alot as well. W2SZ was beat because W1VD had a number of
grids in the log from the 600-800 mile range that SZ missed. The SZ
antenna for that contest was 11/11 at 50/80 feet with down sloping land in
front of the tower toward the southwest. Randy, K5ZD, said that SZ was
the loudest 1 land station in Texas. It was one of the years that I
SZ was in a great location when sections were multipliers, but with grid
squares, Greylock is not as good. KM3T's analysis of Greylock's
shortcomming is correct. The most winnable location that I know of is the
FN00 location that John Lindholm won from a number of years ago. K8GP
seems too far away from the population centers to me.
Dave is right, the foreground of the 20/40 stack for 6 meters is more
critical than 70/140 on 20. However, its better to have the antennas at
the right heights with an uneven ground plane than to have them too high
and miss the skip zone. You might place them on a tower where the house
is in a direction that doesn't matter much. There is one other antenna
consideration for aurora, as the aurora can be very high and a single low
antenna can be the loudest. However, it won't work the
longer auroral paths as well.
I have heard 8's on sporadic E, but it's rare. It can even sound like
The "spraying" in multiple directions might be fine during a strong
opening, but I prefer to use medium gain, keep the antenna moving, find
the direction of an opening by chance, and aim at the opening. Did I say
keep the antenna moving until you find the opening? The opening can move,
so I keep trying a bit north or south of an opening to see if it might be
moving. The toughest trick is to be aiming at a meteor trail at the point
it burns. That is where a wider beamwidth can be helpful.
The Greylock 6 element and my own 7 element antenna are derived from HF
designs done by John Kenny, W1RR, on a mainframe a number of years ago.
Their advantage is a total lack of rear lobes, making listening with
nearby dirty SSB transmitters much easier.
Good Luck, Fred
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