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Old June 8th 11, 01:54 PM posted to rec.radio.amateur.antenna
Michael[_10_] Michael[_10_] is offline
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First recorded activity by RadioBanter: Aug 2009
Posts: 28
Default The Lazy H does not seem to exhibit any gain over a dipole in thereal world


Woohoo! The center fed Lazy H is now working with gain in it's most
favored directions, and it is now consistently out performing the
dipole. I had already pointed the extended double zepp in another
direction, so I'm not sure if the Lazy H is out performing the
extended double zepp.

Below are the following real world lessons I learned from building the
Lazy H wire antenna in the real world. Hopefully it will save future
builders some time.

1) Make sure the 450 ohm ladder line exiting the center of the Lazy H
back to the antenna tuner goes away from the Lazy H at a 90 degree
angle for at least a full wavelength or more or it will skew the
radiation pattern of the antenna.

2) Cut the 450 ohm ladder line going back to the tuner to a length
that is NOT a multiple of a half wavelength on the frequency (or
frequencies) you plan to use the antenna on. In my case since I only
plan to use the Lazy H on 10 meters I found the length required to get
back to the radio room, and then I added length until the total length
landed in between multiples of a 1/2 wave at the antenna design
frequency. The antenna tuner was more easily able to tune the Lazy H
once I did that. When I measured the total length of the ladder line
feeding the Lazy H I included one half of the phasing line that
connected the top and bottom elements.

3) Do not allow sag in the ladder line back to the antenna tuner where
the exiting ladder line falls close to the bottom half of the 450 ohm
phasing line that is used to connect the top and bottom of the Lazy H
or the SWR reading will go up noticeably.

4) The setting on the antenna tuner where a lowest SWR is tuned may
not be the same setting where the receiver receives the strongest
signal from the antenna. This quirk may be specific to my Dentron
MT-3000a tuner and it's internal factory balun.

5) Following number 2 above will probably avoid this situation, but if
your antenna tuner is unable to match the Lazy H at any setting change
the length of the ladder line feeding the Lazy H.

Michael Rawls
KS4HY