Hi Bob,
Thank you for taking the time to input your experience. It's always
important to put things into perspective and not to compare apples with
oranges. Unfortunately, when it comes to antennas, meaningful direct
comparisons are frequently difficult to come by unless you're dealing with
measurements on a professional antenna range.
What you don't mention in your note is probably very important information
to take into consideration too. For example, you state that:
1> With my TA-33, I had 1,700 long-path contacts in
> '91-'92 with only 200 watts.
(a) What you didn't mention was that '91- '92 was only 1 to 2 years off the
peak of the last sunspot cycle and that it probably wouldn't be difficult to
rack up those contacts loading up a piece of wet string "IMHO."
(b) You also didn't mention when you took down the quad and for how long it
was up and how many contacts you made with it.
(c) You also didn't mention if you had actually tuned the quad for max f/b
or max forward gain or, if you even tuned it at all- as opposed to the
"cut-it-to-formula-and-hang-it-up" school of thought.
(d) You also didn't mention if you had all the driven elements tied together
(assuming a 2-el, triband quad) and fed with a common feedline or if they
were fed separately. Yes! It does make a difference in my experience.
Please don't misunderstand me. I am in no way quibbling with your experience
and I really do appreciate your input. However, the conclusions that you
come to need to be taken in context of these other factors (and probably
more that haven't come to mind) in order for me to reach the same conclusions.
My background training in evaluating the conclusions of scientific
experiments naturally makes me very suspicious of results where confounding
conditions were't properly accounted for. And, knowing how non-rigorously
those confounding factors are controlled for in amateur installations, many
"off-the-cuff" conclusions become suspicious indeed.
I would dearly love to be able to agree with you so, please pardon my
skepticism and my request for you to please add additional information- if
you can spare the time.
Thank you in advance for helping to enlighten us all,
Have a really great New Year.
73, Roger, K2JAS
At 08:06 PM 12/29/96 +0000, you wrote:
>Roger,
>
>I replaced my 2-element quad at 37 ft with a Mosley TA-33 and would never
>try a quad again. With my TA-33, I had 1,700 long-path contacts in
>'91-'92 with only 200 watts. I seriously doubt the quad would have been
>up to it. But now I have a Cushcraft A-4, which has a slightly better
>F/B ratio (measured) than the TA-33. The F/B with the Quad was miserable!
>
>73,
>
>Bob, NM7M
>
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