Antenna gain is proportional to boom length for yagi antennas... element
count is only a minor contributor towards gain after boom length is accounted
for.... (the exception to this is the super gain class of antennas, which we
are not discussing here - see Moxon for a good discussion of this topic)...
Anyone claiming that their short boom antenna is the equal/superior of a
longer boom antenna because of their special design, or their loading method,
or their coaxial driven elements, or their karma (whatever), is either
delusional or less than candid...
None of these laws of electromagnetic circuits are a secret... any reliable
text on antennas will discuss the work of Yagi-Uda, NBS, Kraus/W8JK,
Lawson/W2PV, Moxon/G6XN, (and others, including authors active on this
reflector) and will give the formulas for calculating gain/beamwidth, etc...
Certainly, a manufacturer can build an antenna which falls short of the
predicted gain for its boom length, but no manufacturer can build an antenna
which exceeds the predicted gain ... as Tony/K1KP pointed out, a bit of
study on the subject can change your perspective dramatically...
Denny k8do@aol.com
>From k8mr@barf80.nshore.org (Jim Stahl) Wed Jun 12 14:36:35 1996
From: k8mr@barf80.nshore.org (Jim Stahl) (Jim Stahl)
Subject: FD-160
Message-ID: <oZwePD2w165w@barf80.nshore.org>
I'm been putting in my 2 cents worth over the past few years to
try to drum up 160 meter activity in Field Day. Although the
response has been merely whelming, I still consider it a neat
idea for those of us not in the tropical thunderstorm zones.
The suggestion I make for consolidating activity is:
CW on the even GMT hours (CW = 2 letters = even)
SSB on the odd GMT hours (SSB = 3 letters = odd)
Night time hours, obviously!
As a 1-A FD fan the main appeal of 160 is a virgin band to attack
at a time when things often start settling into a rut. It also
gives insurance against the possibility of geomagnetic
disturbances that take out 40 meters and up, resulting in 80
being worked out early. For higher transmitter classes it is an
obvious use for high band stations at night.
Due to an out of town wedding last year, I ended up playing a few
FD hours with the NERDS (WN3K). I beat them into putting up an
inverted-L with 4 elevated radials; I made 9 cw QSOs in 15
minutes running 5 watts. We could have worked a lot more if they
were there!
Back in Ohio the crew at K8BL (7-A) turned one of the high band
stations over to 160 at night and had well over 100 QSOs on SSB,
plus a bunch on CW. I understand they had some good pileups on
sideband.
Summer conditions on 160 are not that much different from 80.
If you have thunderstorms passing overhead, neither will be much
good. On 160 you won't work much DX, but QSOs of a few hundred
miles are no problem. Take along an antenna and give it a shot.
See you all from K8MR in 1-A.
Jim Stahl K8MR k8mr@barf80.nshore.org
----------------------------
Jim Stahl
InterNet: k8mr@barf80.nshore.org
Basic Amateur Radio Frequency, BARF-80 +1 216/237-8208
"Totally devoted to Amateur Radio" - 24 Hrs a day 8/N/1 14.4k-300 baud
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