Comparing antennas is one of those things we all do. We compare them to
our buddy across town or even our buddy 750 miles away.
Well, this week I did some interesting comparisions. As you might know, I
have the ability to dial up my station in the mountains and operate it
remotely. I can see the S-meter remotely.
I compared signals from the remote station on 20 meters while using a 5
element mono band yagi on a 42' boom to my home station which is only an
attic dipole. The mountain station is 50 miles due north of my home QTH.
It was VERY interesting to watch both signals. It was amazing to me
that at times the attic dipole would be as much as 20db better than the 5
element yagi. Most of the time this is not the case, but I would say that
15% of the time the dipole 50 miles further south will beat the 5 element
yagi to stations on the east coast of the USA on 20 meters. On DX, I can
never find a time when the dipole is better.
So a couple of explanations:
1. Being further south may be an advantage especially when the band is
closing. This is a big advantage at times.
2. The station on the mountain is on a hilltop and the pattern produced
by almost all of my antennas is a low fat lobe with few high angle lobes
(if any). This according to TA and YT. My home is on a stream and really
quite low in terms of elevation. I havn't run it in TA (why?), but I
suspect if I did I would have at least one very high angle lobe. So, the
east coasters are quite loud because of their arrival angle.
Anyway... this all goes back to reinforcing N4KG's theory (which I fully
endorse) about having antennas at different heights. It also makes a good
point for not placing to much emphasis on a few comparisons. I think the
only true comparison is one made by one person, with two antennas, at one
QTH. Other comparisons should be done many times and conclusions based
on many experiences. At least that's my take on it.
Just thought it might be interesting to someone.
73
Bill
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