>My only suggestion is to offer quantitative suggestions and not subjective
>ones. K7LXC's paper on tribander comparisons in my mind is the sort of
>thing people should be paying attention to. Not the last paragraph in a
>CQ Magazine product review where the author tells us all how he worked 5
>DL's with 100w in less than an hour.
Gotta agree with Bill here. I'm always amused by stories from hams who
replace one antenna with another and say, "Wow, that new antenna works much
better!" If you don't leave the old antenna up, there's no way to do an
objective comparison. Sure, I could safely claim that my new TH-7 beats the
heck out of my old GAP multiband vertical without doing any quantitative
measurements (some things are obvious), but there's nothing like seeing
10-20 dB or so difference in receive when I switch back and forth between
the antennas. Whenever possible, I like to leave an old antenna up, at least
temporarily, for some comparison measurements with the new antenna. Not
always possible, but it's the only way to quantify the difference. Even
then, it's tough to get reliable measurements when the performance of the
two antennas is closer than a couple of S-units because of propagation
effects, which change second-to-second. You really need two stations set up
close together, like in the K7LXC tests.
Antenna comparisons between two QTHs are nearly hopeless, especially as the
differences get down to a few dB. Too many variables (includig location,
location, location.) As for contests scores, there are *way* too many
variables for doing antenna comparisons. Probably safe to say that Bill's
stacked monobanders on every band are going to be louder than my tribander
and 4-square, but I still think it's worth chasing him -- I could get lucky
on propagation or he could be plagued by thunderstorms! I think there's a
certain threshhold for a competitive antenna system, beyond which operator
skill, station flexibility, propagation and specific circumstances are going
to have a much greater effect than a couple of dB antenna gain (but, hey,
that's probably the *easiest* variable to control, although not the
cheapest.)
73, Dick, WC1M
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