QRZ! Ham Radio 4/QRZ Ham Radio Callsign Database - Volume 4.iso/digests/antenna/940026.txt

Internet Message Format | 1994-11-13 | 14KB

Date: Tue,  8 Feb 94 04:30:27 PST
From: Ham-Ant Mailing List and Newsgroup <[e-mail]>
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Subject: Ham-Ant Digest V94 #26
To: Ham-Ant


Ham-Ant Digest              Tue,  8 Feb 94       Volume 94 : Issue   26

Today's Topics:
                 2m - 70cm combo antenna, the Ray Gun
                    Antenna Erection Aids (2 msgs)
                Copper Dual-Band Super J-Pole Antenna
                 Effective Raditated Power? (2 msgs)
                new radio communications mailing list
                            Rotor problem
                  TEMPEST - Electronic Eavesdropping
                      Through-the-glass antennas

Send Replies or notes for publication to: <[e-mail]>
Send subscription requests to: <[e-mail]>
Problems you can't solve otherwise to [e-mail].

Archives of past issues of the Ham-Ant Digest are available
(by FTP only) from UCSD.Edu in directory "mailarchives/ham-ant".

We trust that readers are intelligent enough to realize that all text
herein consists of personal comments and does not represent the official
policies or positions of any party.  Your mileage may vary.  So there.
----------------------------------------------------------------------

Date: Sun, 6 Feb 1994 13:53:09 GMT
From: netcomsv!netcomsv!bongo![e-mail]
Subject: 2m - 70cm combo antenna, the Ray Gun
To: [e-mail]

In article <[e-mail]> [e-mail] (Steven Jarosh, KA0VYB) writes:
>There was a question sometime back about a combo antenna for 2m and 70cm.
>There were two articles in 73 Mag and I have only found one so far.

    There was an article on a combo 2M/70cM vertical antenna combo
in the March 1990 issue of The Amsat Journal.



--
Julian Macassey, N6ARE  [e-mail] Voice: [phone]
Paper Mail: Apt 225, 975 Hancock Ave, West Hollywood, California 90069-4074

------------------------------

Date: Sun, 6 Feb 1994 14:42:42 GMT
From: netcomsv!netcomsv!bongo![e-mail]
Subject: Antenna Erection Aids
To: [e-mail]

    Recently, there was much correspondence about getting antennas
up in trees. Short of hiring a trained monkey, there are various ways
of getting a line up on a high limb. The favourites seemed to be: bow
and arrow or catapult (sling shot) and spinning (fishing) reel with a
weight.

    The most compact and least troublesome is the catapult and
fishing reel combo. It is small and allows you to reel the line back.
For the standard anti-social contester, it also means being able to do
it alone, so you don't have to be nice to your neighbours or fellow
hams so they will help you get that top band dipole up.
The bow and arrow solution can use a fishing reel, but usually
involves a second person to hold a rod and line while someone does the
Robin Hood stuff. The second person often ends up being a grumpy
spouse who needs no further persuasion that amateur radio is a waste
of time, money and useful house space.

    For those appliance operators that would like the catapult
and reel option but lack the motivation or skills to attach a $10.00
reel to a $10.00 catapult with $00.02 of duct tape there is a
solution.

    For only $39.95, you can buy a fishing reel catapult combo
designed for the job. Call Chicago's Telecom Expert, 812 Nerge Road,
Roselle, Illinois 60172. Phone [phone] (24 Hours). Order the
"Sling-A-Line". All the usual credit cards accepted.

--
Julian Macassey, N6ARE  [e-mail] Voice: [phone]
Paper Mail: Apt 225, 975 Hancock Ave, West Hollywood, California 90069-4074

------------------------------

Date: Tue, 8 Feb 1994 06:26:57 GMT
From: agate!library.ucla.edu!news.ucdavis.edu!chip.ucdavis.edu![e-mail]
Subject: Antenna Erection Aids
To: [e-mail]

Jeffrey D. Angus ([e-mail]) wrote:


:   Why, in my day, we used to have to raise our own cats and  ducks. Finding
:   the pults was a tad tricky, but could be done with the skillful adaptation
:   of a snipe bag.

The real trick to capturing pults in a snipe bag is the pult call.  It is
a little known fact that pults actually have no real ears. They 'hear'
things through ground vibrations they pick up in their bellys.  This
explains why they have evolved a garfield like belly that drags on the
ground.  If you slowly send cq cq cq   cq pult cq pult by stomping your
foot on the ground  you can often attract them.  The only difficulty
being that there has been a recent influx of no-code pults.  For these
it is best to try and hold a large speaker to the ground, but
this only works at much closer range.

Dan
--
*---------------------------------------------------------------------*
* Daniel D. Todd      Packet: KC6UUD@KE6LW.#nocal.ca.usa              *
*                   Internet: [e-mail]                      *
*                 Snail Mail: 1750 Hanover #102                       *
*                             Davis CA 95616                          *
*---------------------------------------------------------------------*
*       I do not speak for the University of California....           *
*       and it sure as hell doesn't speak for me!!                    *
*---------------------------------------------------------------------*


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Date: Tue, 8 Feb 1994 06:52:05 GMT
From: news2.uunet.ca!dmog10.bell.ca!bcocek!vega![e-mail]
Subject: Copper Dual-Band Super J-Pole Antenna
To: [e-mail]

Did someone build that antenna from KA0NAN that was on the April issue
of "73 Amateur Radio Today"? What are your experience with it? Ease of
construction and performance???

Please reply directly to: [e-mail]

Thanks & 73,
Yvan (VE2YDU)


Bell SYGMA, Telecom Solutions
30 Renaud, Loretteville (Qc) CANADA  G2A 2K7
TEL: [phone]          FAX: [phone]
Internet: [e-mail]     HAM: VE2YDU
-----------------------------------------------------------------------
Disclaimer: The opinions expressed here are mine and not my employer's.

------------------------------

Date: 6 Feb 1994 22:20:18 GMT
From: pacbell.com!sgiblab!swrinde!cs.utexas.edu!howland.reston.ans.net!torn!csd.unb.ca!coranto.ucs.mun.ca![e-mail]
Subject: Effective Raditated Power?
To: [e-mail]

[e-mail] (Tom Stein) writes:

>I have a quick question:

>Say I have 40 watts coming out of the back of my radio.  My feedline is
>1.4dB per 100 ft.  I have 100 feet of feedline...  Then my antenna, a 11 el.
>beam has 11dB gain on it.  Can someone tell me what the effective radiated
>power of my system would be?  And a formula would help....

>Tom Stein (N0UJK)

>(Please post only, I do not have e-mail access.)

>Thanks!

40 watts is 16 dBW, subtract 1.4 dB for the feedine, add 11 dB for the
antenna, and your ERP is 25.6 dBW or 365 watts.  X dBW (db referenced to
1 watt) is 10 log Y, where Y is your power in watts, X your power
expressed in dBW, and log is log to the base 10.

Is this what you were looking for?
--
Gerard Dunphy       |"If you don't want to play with old geezers, you
[e-mail] | have to make golf a contact sport!" Calvin

------------------------------

Date: Thu, 3 Feb 1994 13:44:12 GMT
From: mvb.saic.com!unogate!news.service.uci.edu!usc!howland.reston.ans.net!news.cac.psu.edu!news.pop.psu.edu!ra![e-mail]
Subject: Effective Raditated Power?
To: [e-mail]

In article <[e-mail]> [e-mail] (Tom
Stein) writes:
> I have a quick question:
>
> Say I have 40 watts coming out of the back of my radio.  My feedline is
> 1.4dB per 100 ft.  I have 100 feet of feedline...  Then my antenna,
> a 11 el. beam has 11dB gain on it.  Can someone tell me what the
> effective radiated power of my system would be?  And a formula would
> help....
>
> Tom Stein (N0UJK)

   Assuming that the 11 dB gain on the antenna is a `power gain,' the
total gain of your system is -1.4 dB + 11.0 dB = 9.6 dB.  Your ERP is then

     ( 40 W ) ( 10^{9.6/10} ) = 40 (9.12) W = 364.80 W

-Dave
--
David Drumheller                  phone: [phone]
Acoustics Division, Code 7140       fax: [phone]
Naval Research Laboratory
Washington, DC 20375-5350   e-mail: [e-mail]

------------------------------

Date: Mon, 7 Feb 1994 22:08:10 GMT
From: agate!dog.ee.lbl.gov!newshub.nosc.mil!news![e-mail]
Subject: new radio communications mailing list
To: [e-mail]

New RADIO COMMUNICATIONS MAILING LIST

We have started a new mailing list for professionals
in the radio communications field.  If you make your
living in this field, or think you might, then
you are invited to subscribe.  Relevant topics are:
antenna design, radio propagation, hardware design,
software design, FCC rules, market trends, military
requirements, and so forth.

Hobby-related questions should remain with the
rec.radio.amateur.* newsgroups.

To subscribe, send a message to:
[e-mail]
I will reply with an informational message.

SOME PREVIOUS SUBSCRIBERS HAVE APPARENTLY SENT
THEIR MESSAGE TO:  [e-mail].  I HAVE
NOT RECEIVED THESE MESSAGES.  If you have
subscribed but have not received an informational
message from me, try sending another message.

Brett F. Martin
Naval Command, Control, and Ocean Surveillance Center
San Diego CA

[e-mail]

------------------------------

Date: Thu, 3 Feb 1994 13:58:25 GMT
From: mvb.saic.com!unogate!news.service.uci.edu!usc!howland.reston.ans.net!vixen.cso.uiuc.edu!uwm.edu!msuinfo!uchinews!att-out!cbnewsh![e-mail]
Subject: Rotor problem
To: [e-mail]

My old Alliance HD73 rotor developed indicator problems after the ice storm
a couple of weeks ago.  I'm wondering if anyone can suggest what failure could
account for these symptoms.  I normally leave the antennas facing west when
not in use.  When the antennas are west, the direction meter indicates
correctly.  I take this to mean that the wiring is intact.  If I turn more
than a few degress CCW toward the south stop, the meter will drop to zero and
will stay there while the rotor turns all the way to south.  If I turn more
than a few degrees CW, the meter will peg at full scale and stay there for the
full rotation to the other south stop.

This rotor has been in use since 1979 carrying 2 or 3 antennas in a mast mount
configuration.  I am considering whether it is time to replace it.  I no
longer see the HD73 in catalogs so an exact replacement or even spare parts
might be hard to get.  Any experience or suggestions on a good unit?
I have used the CDR(now HyGain) CD45 in the past and I do not think it is
heavy duty enough.
John K4BNC
~

------------------------------

Date: 6 Feb 1994 21:08:33 GMT
From: pacbell.com!sgiblab!sdd.hp.com!math.ohio-state.edu!howland.reston.ans.net!EU.net!uknet!bhamcs![e-mail]
Subject: TEMPEST - Electronic Eavesdropping
To: [e-mail]

Transient Electromagnetic Pulse Emanation Standard (TEMPEST) is the
US standard defining the amount of electromagnetic radiation that a
device may emit without compromising the information it is
processing.

In the US it not illegal to posess TEMPEST-surveillance equipment but
it is illegal to take appropriate counter-measures to prevent
surveillance. The US government has refused to release details of its
TEMPEST research and has restricted the dissemination of independent
research by classifying it.

The US Drug Enforcement Agency (DEA) makes use of TEMPEST secured
electronics and computers as they believe that the drug cartels may
possess surveillance equipment.

I am interested in gathering comments on the social, legal, ethical,
and technical aspects of use of TEMPEST surveillance equipment in
the US and Europe with the aim of including it in a discussion
of the threats to computer/digital systems.



Please reply by E-mail. I will provide a summary to anybody who
requests one.

thanks,     - Rob Jackson

(more information on TEMPEST can be found in the paper
 "Eavesdropping On the Electromagnetic Emanations of Digital
  Equipment: The Laws of Canada, England, and the US" by
  Cristopher Seline - available on FTP from csrc.ncsl.nist.gov)

------------------------------

Date: Thu, 3 Feb 1994 13:14:07 GMT
From: mvb.saic.com!unogate!news.service.uci.edu!usc!howland.reston.ans.net!newsserver.jvnc.net!news.cac.psu.edu!news.pop.psu.edu!ra![e-mail]
Subject: Through-the-glass antennas
To: [e-mail]

   This past year I bought a new car, a 1993 Saturn.  I want to install a
2-meter through-the-glass antenna on the rear window. However, I noticed
that the top of the window is tinted opaque black.  Question: is this
tinting metallic or otherwise conductive?  If it is, then I guess a
though-the-glass antenna is out of the question.  Anybody know anything
about this?

Dave
--
David Drumheller, KA3QBQ          phone: [phone]
Acoustics Division, Code 7140       fax: [phone]
Naval Research Laboratory
Washington, DC 20375-5350   e-mail: [e-mail]

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End of Ham-Ant Digest V94 #26
******************************