----- Original Message -----
From: "Tom W8JI" <w8ji@w8ji.com>
To: "Carl" <km1h@jeremy.mv.com>
Cc: <topband@contesting.com>
Sent: Sunday, December 16, 2012 11:26 AM
Subject: Re: Topband: raised radials
Or the person on here who went from an extensive radial system to a full
screen claimed a 5dB improvement but now denys the possibility. Its in
the TB archives from 1998.
Carl,
Please try to stop that silly disappointing long-time practice of
re-writing what other people say just to start a fight.
I ****NEVER**** said I didn't measure a 5 dB change, or that some system
changes can't produce a 5 dB (or even a 30 dB) change when someone does
something terribly wrong in a system.
** Some time spent in the archives could be an eye opener to many on here.
Im far from looking for a fight as you claim, just get some things
clarified.
What I am saying is:
1.) Your claim you felt you had a ~10 dB change, based on your feelings of
how much a signal must change busting a pileup, when you added some screen
to a system is pretty silly. It is a test at least days apart on sky wave
with no data reference at all. It is typical junk science of
** Thats about what Id expect from you, demeaning comments when you dont
have a clue what I did. The radials only were for over a year of daily
operating so I had a pretty decent feel for the bands variances. This was a
decade before Topband came along. The screen went down one day and by sunset
I was active again, didnt miss a beat. The group of friends I worked with on
a private 222MHz repeater all commented on the improvement since I was
regularly beating them in pileups and they had good vertical installations.
the worse kind.
If your original ground system did not have severe issues, the imagined
"10 dB" would be impossible.
** You are very wrong since you remain hung up on only part of the picture.
2.) Broadcast stations use a screen as a connection point and mechanical
convenience, NOT to improve signal or effiency.
** Wrong again since you conveniently leave out the rest of the reason.
The screen allows people to
walk near the tower base without falling over wires, and it allows
connecting boxes, fences, posts, and other things into the radials no
matter where they are located near the base. They also usually use stone
at the base, and weedkiller...so we can't assume everything they do is for
"signal reasons".
** Nope and that is a completely different install than what I am discussing
where the close in base screen plus elevated radials is used as a necessity
for mainly financial reasons.
If you take some time to read FCC guidelines, the screen is actually
optional.
** Ive read it and you are changing the subject again
If you read Lewis, Brown, and Epstein, instead of misreading
Topband archives,
** My reading suggests quite different.
you will see they ALSO said the screen does not when a
adequate number and length of radials is present.
Please stop the silly childish misrepresentations.
73 Tom
** Stop the demeaning and subject switching/slanting whenever you get into a
jam Tom. This is not Eham or QTH, there are many educated readers on here
that can see right thru it
Carl
KM1H.
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