*** Reply to note of 10/17/96 13:10
K4SB made several claims with which I disagree.
If I remember correctly, the breakdown voltage of solid dielectric RG8 and
RG-213 is closer to 5000V. Foam dielectric cable breaks down at around 1500V.
The capacitance per foot of 50 ohm cable is 28 to 30 pF/foot and
the capacitance per foot of 75 ohm cable is 20 to 22 pF/foot, depending on
which cable is used.
A high quality capacitor will dissipate NO POWER and is nearly lossless.
Maximum power transfer occurs with a conjugate match. This is when the
source RESISTANCE and load resistance are equal and the source REACTANCE
is equal in magnitude but opposite in sign.
Therefore, raising the radiation resistance of an inverted L by lengthening
it and cancelling the inductive reactance with an equal capacitive reactance
is an effective and simple means of achieving maximum power transfer to this
type of antenna.
The folded mono-pole concept mentioned by K4SB is another means of achieving
a higher feed point impedance.
de N4KG - Tom
>From jcarter@mailhost2.csusm.edu (Jerry A. Carter) Fri Oct 18 19:25:00 1996
From: jcarter@mailhost2.csusm.edu (Jerry A. Carter) (Jerry A. Carter)
Subject: Five Band Worked All States
Message-ID: <2.2.32.19961018182500.006747dc@mailhost2.csusm.edu>
Hi all,
I've been working towards 5BWAS for more years than I wish to count. I find
that I have 10, 20, 40, 80, and even 17 completed. 15 meters is almost done
and I lack only 10 states to be confirmed on that band. The states I need are:
AZ DE ME MD MO MT NH ND RI UT
As the average age of most of my friends is DEAD, I thought I'b better do
something to help this thing along hence this posting.
I propose to be on the air between the hours of 1800-2000 UTC everyday that
I can, which should be 5 out of 7 at least. I will be as close to 21.300 as
I can get and will call CQ frequently and of course will work anyone from
anywhere who responds. For those from the states I need I will initiate a
QSL card and a SASE. I have a 2 element Quad up 70 feet and I should be
able to hear you if the band is open at all. I can also run full power if
you are having difficulty with my normal 100 watt signal.
If anyone knows of a time that they can get into California on 15 on a time
other than the above, send me an email as to when and on what frequency I
might find you.
Just a note of explanation: The jcarter@....address is my wife's as she has
the account; however, you can reach me at my re-mail address of:
wa6yoo@amsat.org
Thanks for the bandwidth.
73,
HARRY A. HODGES, WA6YOO
Escondido, CA
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