Snip of an ongoing conversation on this topic, of general interest...
<snip>.....
On the Penetrox... I stuck the vom probes in it on the X 1meg scale, and
there was NO conductivity... You had me worried there for a minute, as I
thought you implied that they had changed the formulation....I neither
expected, nor wanted any conductivity... I checked the conductivity of all
the assembled and gooped joints on the antenna, and they are < 0.10 ohms,
which is low as I can measure without resorting to a welding machine and
voltage probes...
I also checked the klm, copper sheen, goop and it has no conductivity until
you get the probes about 0.010" apart, then there is a small current
flow....probably due to squeezing the copper powder into contact... However,
I consider this to be undesireable.... The purpose of joint goop is not to
be conductive... It is, in fact, the exact opposite... It is to
prevent/insulate ionizing electron flow between metal surfaces and conductive
moisture in the joint space...It is _supposed_ to be an insulator, it is
supposed to fill any gap in the joint excluding air and moisture, and it is
supposed to suppress ion currents... Making it conductive is counter to its
purpose.... . Allowing ion driven, electron flow across a gap will erode your
metals and turn them to powder.... You want free electron flow to occur only
between solid metal surfaces in intimate contact and which have squeezed the
goop from between them...
<snip ... personal ramblings not of general interest snip ....>
I am suspicious of any goop that has powdered metal in it for two reasons...
The metal particles act like spacers between the metal surfaces you are
trying to bring into intimate contact, thus preventing that contact.... and
because, as the 'grease' component vaporizes and disappears with time, the
enormous surface area of the powdered metal is sure to adsorb moisture,
oxidize, and become more resistive....Now you have a resistive medium
separating your metal surfaces ( a series resistor) - an undesireable
situation at any frequency....
<end snip>....
>From Dr. Eugene Zimmerman" <ezimmerm@DGS.dgsys.com Fri Nov 17 22:36:50 1995
From: Dr. Eugene Zimmerman" <ezimmerm@DGS.dgsys.com (Dr. Eugene Zimmerman)
Subject: TS-930/940 and 2nd Antenna
Message-ID: <Pine.SOL.3.91.951117172553.25624B-100000@DGS>
In case you are look for a source of these oddball DIN connectors, try my
local source
The RF Connection
Gaithersburg, MD
800-783-2666
Remember to tell him it is for the TS930/940.
His prices are lots better than ICOMs.
He also has lots of other connectors, both easy to get and not so easy to
get, and carries various kinds of feedlines.
And more important, he knows what he is doing - a rare commodity these days.
73 Gene W3ZZ
> N4ZR wrote:
>
> >The commonly available 8-pin DIN plug has a keyway that is said to be a
> >different size than that on the jack on the TS-930, 430 and 440. It is
> >reportedly quite easy to break the socket if you try to plug in the generic
> >plug, and a real bear to replace.
>
> AD1C wrote:
>
> The real difference is that the CORRECT connector has the pins arranged in
> a horseshoe pattern.....<snip>
> 73 - Jim AD1C
>
>From jreid@aloha.net (Jim Reid) Fri Nov 17 23:39:28 1995
From: jreid@aloha.net (Jim Reid) (Jim Reid)
Subject: Antanna R-sub-r and Ground Loss
Message-ID: <199511172339.NAA29724@hookomo.aloha.net>
This question has been asked:
Rr is calculated to be: 19.29 -j8.34, does this mean that it is accepting only
about HALF of the power of the first antenna?
An answer provided:
"Antenna #1 would have a 3 dB advantage only if the currents driving
the two antennas were the same (Power = I^2 R). However, in
practice, real radio transmitters/amplifiers deliver constant
power (not current) output into reasonable loads, i.e. loads that
can be matched with the transmitter output matching network. Therefore,
the total powers radiated by the two antennas are the same, regardless of
the antenna impedances, assuming there is no other loss in the antennas."
But, I believe ( and I hope I am wrong!) that
the power matched from the 50 ohm transmitter source by the tuner,
is still divided between the I-squared-R power in the real part of the
calculated antenna impedance (the 19.20 ohms) and the ground loss
which would be 50 minus 19.2, or about 31 ohms, and, yes, if true,
61% of the transmitter power is dissipated in ground loss, and only
39% radiated, or coupled into propogation, or the signal strength would
be down 4 dB from the antenna with a 50 ohm radiation resistance. I know
this is what happens with short verticals, and why verticals less than
1/2 wave tall (length of the actulal radiating metal, regardless of traps,
loading
coils and capacity hats) are not particularly efficient radiators. Some of them
have R-sub-r's of only a few ohms, even tho the VSWR shows to be very
low! The ground does take most of the power.
I hope I am wrong about this, and that a yagi, since the radiating elements
are dipoles, and hopefully balanced, does not loose power to ground
dissipation losses.
If I am wrong, then what is the advantage to a full length, that is a true
1/2 wave long driven element on a so called full sized yagi? (Since
we can get just about any length of metal, center fed, to "load up"
and radiate using a tuner?) Always heard that the full sized yagi was
more efficient, if so, then where does the power go that is lost to
inefficiency in a yagi with shorter elements loaded with traps or
whatever?
73, Jim, AH6NB
>From gmaples@iquest.com (G. Mike Maples) Sat Nov 18 00:03:36 1995
From: gmaples@iquest.com (G. Mike Maples) (G. Mike Maples)
Subject: Howdie
Message-ID: <199511180003.SAA23557@vespucci.iquest.com>
Dont thk I've talked to u since ypu sent the msg and the files via internet
... All went FB ... No hitch at all.. Been A LONG Week ... GLAD its FRIDAY
..>>> CUL >>> MM
>From Larry Crim <wz4f@iquest.com> Sat Nov 18 00:08:41 1995
From: Larry Crim <wz4f@iquest.com> (Larry Crim)
Subject: WHERE'S THE BEEF?
Message-ID: <Pine.BSD.3.91.951117175923.22881A-100000@vespucci.iquest.com>
The ACTIVE ZONES boxes in Oct. '95 CQ are in error. K3EST sent me an
E-mail and told me that they would be corrected in K1AR's December
column. Got my CQ today and no mention of the errors. I guess he just
forgot. Think the boxes are a great idea, but they should be correct. There
was a thread on this earlier. BTW, the SSB ACTIVE ZONES boxes in Sept.
'95 are also all screwed-up.
73,
Larry
wz4f@iquest.com
On Fri, 17 Nov 1995, Douglas S. Zwiebel wrote:
> I'm sitting here looking over my October 1995 CQ magazine on page 118;
> you know, the ACTIVE ZONES box. I find it really amazing at what it
> (doesn't) take to make some of these boxes and, more specifically,
> how little competition there is in zones 3 & 25. Take a look at these
> comparisons:
>
> ZONE top score 5th score % of #1 10th score % of #1
>
> 5 4.037 M 3.177 M 78.7% 2.317 M 57.4%
>
> 4 2.021 M 1.496 M 74.0% 0.607 M 30.0%
>
> 3 1.611 M 0.859 M 53.3% 0.382 M 23.7%
>
> 14 3.469 M 2.800 M 80.7% 1.987 M 57.3%
>
> 15 3.311 M 2.285 M 69.0% 1.452 M 43.8%
>
> 25 2.389 M 1.538 M 64.4% 0.578 M 24.2%
>
> And to make it even worse in terms of real competition, 3 of the 10
> "box" scores for Zone 3 were LOW POWER entrants. Any ideas here? Are
> W6 ordinances so restrictive and so widespread that nobody has any
> antennas? Was EVERYBODY on a DxPedition? Come on W6 contest clubs,
> let's get some local activity going. You only need 23% of the top
> score to make the box!
>
> And what about Zone 4 (lots of room and big open spaces there). A
> Zone 4 guy only needed 30% of the top score to make the box!
>
> I know I have my unavoidable EAST COAST bias, but I think that in doing
> this type of comparison, I have objectively negated that slant. From a
> marketing point of view, this is VERY SAD and forebodes our demise!
>
> Come on you "little pistols" and contest clubs. Stir up the troops,
> get on in the contest, and SEND IN YOUR LOG. You CAN make the BOX!
>
> de Doug KR2Q@mcimail.com
>
>
>From claver@noao.edu (Chuck Claver) Sat Nov 18 00:24:33 1995
From: claver@noao.edu (Chuck Claver) (Chuck Claver)
Subject: Antanna R-sub-r and Ground Loss
Message-ID: <9511180024.AA25969@taco.tuc.noao.edu>
Jim, AH6NB, wrote:
"But, I believe ( and I hope I am wrong!)... ...and the ground loss
which would be 50 minus 19.2, or about 31 ohms..."
This is not how its done. First, in a Yagi antenna there are no ground losses
at the feed point, like you would have for a vertical. A dipole, or driven
element is a balanced radiator and does not collect return currents from
the ground. Second if the above were true then we would be in big trouble any
time we wanted to match a 200 ohm input impedance to a 50 ohm feed line -
those 4:1 baluns would be getting awfuly hot with a KW to them. Impedance
matching through a transformer (balun) or antenna tuner does not necissarily
imply increased loss.
The loss resistance of an antenna are independant of the impedance of
the feedline. The are a function of the quality and type of meterial and
construction of the driven element. The importance of the loss resistance
is determined by the amount of current flowing through it, which is determined
by P=I^2R - where R is the sum of the feed and loss resistances. Once the
current is know the amount of power loss is estimated using P=I^2R again, this
time R is only the loss resistance.
The advantage of a full sized element is due to the fact it radiation resistance
is higher than for a shortened element of the same style. As the radiation
resistance goes down the importance of loss resistance goes up - assuming
constant loss resistance. Furthermore, depending on how you shorten an element
will alter what part of the current distribution does the radiating. For
example a top loaded vertical is more efficient than a base loaded vertical.
This is partly because the top loaded vertical the radiation comes from the
earliest part of the current phase distribution (I=cos(phase)) - say from
0 through 50 degrees. Where a base loaded vertical of the same electrical
length (50 degrees) radiates from the current distrubition between 40 and
90 degrees. The cosine function has maximum amplitude at 0 degrees and minimum
at 90. Thus the percent of radiated energy relative to a fullsize element
is higher for the top versus botom loaded antenna, but still smaller than the
full size element.
ON4UN's book on low band DXing has a good discusion of what goes into the
efficiency of an antenna.
I hope I have not confused but informed,
Cheers to all,
de NJ6D Chuck Claver
>From Larry Crim <wz4f@iquest.com> Sat Nov 18 00:29:17 1995
From: Larry Crim <wz4f@iquest.com> (Larry Crim)
Subject: BEEF stew clarifer (fwd)
Message-ID: <Pine.BSD.3.91.951117182425.22881D-100000@vespucci.iquest.com>
DOUG!
Those damn ACTIVE ZONES boxes are all screwed-up!!!!! I should know I
should be listed as the #5 zone 4 in CQWW SSB and #6 in CQWW CW. I also
know of at least 3 other guys who were ommitted. Seems that the CQ
software thought that if you had a 4-land call, you were in zone 5. That
left out a lot of guys! Dont know about the zone 3 problems. Look 'em
up in the results---you'll see. You may want to stop this thread before
you look like a goof. I told K3EST about the errors. He said thanks,
and that he would correct them in John Dorr's December column. But, he
didn't. I guess that would violate one of the tenets of journalism:
"If you make a mistake, that's one mistake...If you admit it, that's two
mistakes." He should have made the errors public...that might have saved
you some key-strokes!
73,
Larry WZ4F
wz4f@iquest.com
On Fri, 17 Nov 1995, Douglas S. Zwiebel wrote:
> Hi guys....I have received a couple replies about my comparison and
> based on those replies, I guess I did NOT make clear WHAT I am
> comparing.
>
> 1) I am NOT comparing the SCORES from one zone to another zone.
> 2) I AM comparing, on a RELATIVE SCALE, what it take WITHIN ONE ZONE,
> to make the active zone box. How did the 10th place guy IN THAT
> ZONE do compared to the first place guy IN THAT SAME ZONE.
> 3) Using these RELATIVE percentages, I am saying that there is less
> COMPETITION (not less ability, nor less absolute score) within
> certain zones.
> 4) I want to know why there less COMPETITION (comparing 1st to 10th)
> WITHIN THAT ZONE.
> 5) The percentages apply to that line (zone) only. There is NO inter-
> zone comparison shown. Everything listed percentage-wise is
> INTRAzone.
> 6) Because I am doing INTRAzone comparisons, I felt that I had negated
> my "east coast" bias.
>
> Sorry for the confusion I caused to those who did not fully comprehend
> my original intention. I trust that this will clarify the TABLE I posted,
> and the question(s) I am trying to find an answer to.
>
> de Doug KR2Q@mcimail.com
>
>
>From Larry Crim <wz4f@iquest.com> Sat Nov 18 01:28:59 1995
From: Larry Crim <wz4f@iquest.com> (Larry Crim)
Subject: BEEF stew clarifer
Message-ID: <Pine.BSD.3.91.951117192659.28914A-100000@vespucci.iquest.com>
BTW Doug,
Someone just told me that you are on the CQWW committee that certifies
the contest results. Is that true?
CU,
Larry WZ4F
wz4f@iquest.com
On Fri, 17 Nov 1995, Douglas S. Zwiebel wrote:
> Hi guys....I have received a couple replies about my comparison and
> based on those replies, I guess I did NOT make clear WHAT I am
> comparing.
>
> 1) I am NOT comparing the SCORES from one zone to another zone.
> 2) I AM comparing, on a RELATIVE SCALE, what it take WITHIN ONE ZONE,
> to make the active zone box. How did the 10th place guy IN THAT
> ZONE do compared to the first place guy IN THAT SAME ZONE.
> 3) Using these RELATIVE percentages, I am saying that there is less
> COMPETITION (not less ability, nor less absolute score) within
> certain zones.
> 4) I want to know why there less COMPETITION (comparing 1st to 10th)
> WITHIN THAT ZONE.
> 5) The percentages apply to that line (zone) only. There is NO inter-
> zone comparison shown. Everything listed percentage-wise is
> INTRAzone.
> 6) Because I am doing INTRAzone comparisons, I felt that I had negated
> my "east coast" bias.
>
> Sorry for the confusion I caused to those who did not fully comprehend
> my original intention. I trust that this will clarify the TABLE I posted,
> and the question(s) I am trying to find an answer to.
>
> de Doug KR2Q@mcimail.com
>
>
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