While paging through an "E & B Marine" catalogue, I happened upon the now
famous "Loose Tension Guage" for $39.99 plus shipping. The part number for
the 3/16" to 9/32" one which we've all been talking about is: 1004-8577 and
can be ordered by calling: 800/262-8464. I've had good luck with this outfit
for sailboat parts, etc., but have no connection with the company. They were
in stock this morning when I placed my order (always get 'em in the log
before making the spot!).
John, K0IJL
>From K0RC - Robert Chudek <K0RC@pclink.com> Tue Apr 30 03:21:46 1996
From: K0RC - Robert Chudek <K0RC@pclink.com> (K0RC - Robert Chudek)
Subject: Rain Static
Message-ID: <199604300225.VAA01487@pclink.com>
Last summer I experienced the rain static problem at my new
QTH with my Mosley PRO-67B up 90 feet (insulated driven elements
and plumbers delight parasitic elements). I quickly ran outside
and discovered it was not raining. I noticed an approaching
storm cell a mile or two in "front" of the yagi. When I turned
the yagi away from the storm cell, the static went from +10 dB
over S-9 on the meter to inaudible! I concluded the storm cell
was internally generating this wide band noise. (The noise sounds
like a loud waterfall, opposed to random lightning crashes. It
builds from individual, infrequent "pops" in the receiver to a
steady "roar" at the peak.)
I have also experienced precipitation static both during the
summer rain showers and winter snow storms. And I have witnessed
electrical discharges across my 4" compression guy insulators during
a breezy, dry summer day!
FWIW
Robert Chudek - K0RC
k0rc@pclink.com
At 09:48 AM 4/29/96 -0700, Ward, N0AX wrote:
>
>The sense that I'm getting is that it's a single "perceived" problem made
>of up at least two sub-problems.
>
>First of all, there's the all-the-time, ongoing corona discharge, however
>slight, of the continuous earth/air charge transfer process. Due to
>changes in the potential difference during storms, this noise source
>increases in intensity during storms, even if there's no precip at all.
>
>Second, there's the noise cause by drops or flakes with a charge hitting
>the grounded element. The intensity of this source isn't really well
>defined, nor is the process all that well understood.
>
>Third is a mixed bag associated with whether or not there's a DC path to
>ground from the antenna, whether the wind is blowing, how large the
>antenna is, how tall it is, whether there are adjacent antennas, etc.
>
>If I had to call it today, I'd take W0UN's advice and ground everything,
>and then try to place a tall mast above any high antenna to try and move
>the corona discharge point as far away from the antenna itself as
>possible. The insulation issue is probably not very important. If I get
>a chance, I'll browse the IRE/IEEE indices for stuff on precip and
>atmospheric static.
>
>73, Ward N0AX
>
>
>From PETER GRILLO <ah3c@burgoyne.com> Tue Apr 30 10:26:13 1996
From: PETER GRILLO <ah3c@burgoyne.com> (PETER GRILLO)
Subject: Room at Stauffer's
Message-ID: <199604300326.VAA25161@burgoyne.com>
Contester or DXer -
N4OGW and I are looking for one more to share a room at Dayton. It is
Thursday evening through Sunday Morning. Will advise particulars on cost
upon inquiry....
73 - Pete, AH3C
>From John Brosnahan <broz@csn.net> Tue Apr 30 04:42:36 1996
From: John Brosnahan <broz@csn.net> (John Brosnahan)
Subject: Hardline connectors
Message-ID: <199604300342.VAA16933@lynx.csn.net>
>73, Ed
>
>P.S. You CANNOT merely solder the center wires together and put a hose clamp
>over it and tape it up. Their is such a thing as the dialectric of the
insulating
>material.
>-------------------------------------
>Name: ed sleight
>E-mail: k4sb@avana.net
>Time: 03:25:36
But you can splice the center conductors together
with the right size brass tubing from the hobby store
(ID of the tubing should match the OD of the center
conductor), which does increase the center conductor
diameter at this point. Then replace the dielectric material
with some scrap stuff and then take the proper size
of aluminum tubing to fit OVER the shield and slit it
in half and clamp it with a few hose clamps. Make
the tubing long enough to grip the shield for 3 or 4
inches on either side of the splice to provide mechanical
strength. (I have also added some RTV around the
dielectric on occasion to fill up any air spaces if
jumidity is a problem.) Now the ID of the aluminum
tubing is equal to the original shield OD, and the
center/shield ratio is still aproximately the same and the
dielectric is the same and therefore the impedance will be
the same for the splice as it is for the rest of the cable. I
have done this with various versions of hardline
from 50 ohms to 100 ohms and from 1/2 inch to 7/8 inch
and have had excellent results when run an HP Time
Domain Reflectometer.
Note: The TDR is a very sensitive device. It shows huge
bumps on a PL-259 junction and even shows the minor
bumps inside a BNC connector (which is exactly the
same as an N connector! (except for the mechanical
part) Don't believe me? Take an N male connector and
pus it onto a BNC female. The internals are exactly the
same and this is an old timers trick that can be used
in a pinch. Only difference is the mechanical engagement.
ie An N connector won't handle any more power than a
BNC!
So with the proper knowledge and some care it
is possible to splice hardline. The hose clamps
make big lumps but when covered with heavy
duty heat shrink that has sealant (from the factory)
this connection can be made to be totally waterproof.
Your mileage may vary (according to your skill).
73 John W0UN
John Brosnahan
La Salle Research Corp 24115 WCR 40 La Salle, CO 80645 USA
voice 970-284-6602 fax 970-284-0979 email broz@csn.net
>From De Syam <syam@Glue.umd.edu> Tue Apr 30 05:12:09 1996
From: De Syam <syam@Glue.umd.edu> (De Syam)
Subject: Yagi Balls
Message-ID: <Pine.SOL.3.91.960430000900.2870B-100000@logo.eng.umd.edu>
On Mon, 29 Apr 1996, Ward Silver wrote:
> >
>
> Corona discharge was the reason for the invention of the quad antenna by
> Clarence Moore in the late 40's (1949?) at HCJB near Quito, Ecuador. This
> high-altitude site had such thin air that the high-power SW transmitter of
> several kW caused ferocious corona at the element tips of the yagi
> originally installed. So ferocious that the metal melted and slowly
> consumed the elements! After trying all sorts of things like metal balls,
> loops, etc. Clarence hit upon the idea of an antenna element with no
> ends...and thus the quad was born. There's quite a good relation of the
> full story in Bill Orr's book on quads.
>
It was my great pleasure to be present several years ago at a ceremony at
the Ecuadorian Embassy in Washington at which Clarence Moore (W9??? from
Indiana - now SK) was presented with an award and the lifetime call of HC1JB
for his putting Ecuador on the world scientific map by his invention of
the quad antenna.
Very 73,
Fred Laun, K3ZO
>From David Robbins <ky1h@berkshire.net> Tue Apr 30 10:42:40 1996
From: David Robbins <ky1h@berkshire.net> (David Robbins)
Subject: corona balls
References: <199604292144.VAA17843@mailhost.worldnet.att.net>
Message-ID: <3185E090.1703@berkshire.net>
Douglas Zwiebel wrote:
> PS...am I really that old that nobody else knows that Telrex antennas used
> corona ball? :-(
>
> de Doug KR2Q
don't worry doug, i have several big telrex's with balls. of course i
was thinking of donating them to the smithsonian for a display on
ancient communications methods, but for now they are still up in the
air.
and they are just as noisy in snow/rain as any other antenna.
73, dave
--
ky1h@berkshire.net or robbins@berkshire.net
http://www.berkshire.net/~robbins/ky1h.html
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