QRZ! Ham Radio 4/QRZ Ham Radio Callsign Database - Volume 4.iso/digests/antenna/940119.txt

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

Date: Mon, 25 Apr 94 04:30:16 PDT
From: Ham-Ant Mailing List and Newsgroup <[e-mail]>
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Reply-To: [e-mail]
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Subject: Ham-Ant Digest V94 #119
To: Ham-Ant


Ham-Ant Digest              Mon, 25 Apr 94       Volume 94 : Issue  119

Today's Topics:
                  AEA IsoLoop vs. MFJ 1786 HI Q Loop
                          Best city antenna
              Combined mobile phone/VHF/radio antenna???
                     help with packet antenna..
                   phased vertical array software?
                      portable antenna for NVIS?
                     Transceivers in modern cars

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Archives of past issues of the Ham-Ant Digest are available
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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.
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Date: 25 Apr 94 03:38:07 GMT
From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!noc.near.net!news.delphi.com!BIX.com![e-mail]
Subject: AEA IsoLoop vs. MFJ 1786 HI Q Loop
To: [e-mail]

Thanks for the response.  I appreciate your interest.

I just built the May QST loop this weekend.  Unfortunately,  the
capacitor I had only allows running QRP.  I designed mine so it
can be mounted either horizontally or vertically.

So far, the vertical orientation seems best,  as I
can't elevate it the recommended 1/2 wavelength.  It receives
very well.  Only a few QSOs so far with 10 - 20 watts.

I couldn't find the comparison in QST.  I'll look again.

Thanks,  73s
Dick McCoy N4UN

[e-mail]

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Date: Mon, 25 Apr 1994 01:29:11 GMT
From: netcomsv!netcom.com![e-mail]
Subject: Best city antenna
To: [e-mail]

[e-mail] wrote:
: [e-mail] wrote: [stuff deleted]

:     Fine.  you people are of absolutely no help.  Not one response.
: I guess I'll just go back to newsgroups that are actually helpful.
:                     Stan "Bye, Bye" Kwong

If you not happy the with the responses ask for a refund.. How much did
you pay again?
Guy, you left <no> helpfull information at all..  What the hell do you
want to do with this antenna?  What band?  If it's scanning go to
rec.scanners or is it rec.radio.scanners?  What power to you want to run
- what modes? etc....

Ryan "Bite me" Radio d00d    [e-mail]

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Date: 25 Apr 1994 08:32:42 GMT
From: ihnp4.ucsd.edu!agate!howland.reston.ans.net!pipex!sunic!news.funet.fi!nntp.hut.fi!vipunen.hut.fi![e-mail]
Subject: Combined mobile phone/VHF/radio antenna???
To: [e-mail]

I'm all new to the world of antennas and therefore need information
on the following:

A company in Finland manufactures a combined mobile phone/VHF/radio
antenna for use on boats, in cars or wherever. The antenna is 37 cm
long and made of steel rod. It covers frequencies for mobile phone:
860-980 MHz and 435-485 MHz, marine VHF 140-175 MHz and radio 0-110 MHz
receiving. The electronics are built into a filter box of about 6*6 cm.
The connectors are all BNC connectors.

I would like to use a system like this on my sailing boat but I'm not sure
it stands up to its promises.

Does this sound like a good system? What level of damping does a system
like this have? And compared to three different antennas mounted on the
top of the mast, does an antenna like this mounted on the same place
provide the same range of sending and receiving? What kind of cabling do
I need?

Please tell me the advantages and disadvantages of a system like this.
I'm also interested in the physics of such a system.

Thanks in advance

Len
[e-mail]

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Date: Mon, 25 Apr 1994 01:40:20 GMT
From: netcomsv!netcom.com![e-mail]
Subject: help with packet antenna..
To: [e-mail]

[e-mail] wrote:
: Hi Everyone:

: I am running a packet TNC on 2 mt radio.  Right now i have ground-plane
: antenna.  It is okay for the time being.  I was wondering is there
: any better antenna specifically for packet on 2 mt radio.  If you have
: any suggestion, please post here or email to me.

Welp, my fealing, and the general consensus where I'm operating is that a
vertical antenna of darn near any kind is that way to go.  With beams
other directional antennas you may reach the BBS/other party great, but
some guy a couple miles off the back of the antenna wont hear you, and
you can end up both transmiting at the same time, etc.  I'm using a
Commet 2m/70cm dual band 5'11 (or so) antenna (don't remember the model),
but there are <alot> of differant antennas working great on packet.  Are
you having any problems with what you have now, or is there a particular
way you want to improve the way things are now?  Are you using a DCD
circuit w/ open squelch on your radio?

Ryan    [e-mail]

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Date: Mon, 25 Apr 1994 09:26:08 GMT
From: ihnp4.ucsd.edu!galaxy.ucr.edu!library.ucla.edu!europa.eng.gtefsd.com!howland.reston.ans.net!cs.utexas.edu!convex!news.duke.edu!eff!news.kei.com!world![e-mail]
Subject: phased vertical array software?
To: [e-mail]

Can anyone provide pointers to freeware or shareware for computing
and/or displaying the signal patterns of phased vertical arrays?

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Date: 25 Apr 1994 02:50:03 -0400
From: ihnp4.ucsd.edu!library.ucla.edu!europa.eng.gtefsd.com!news.ans.net!hp81.prod.aol.net!search01.news.aol.com![e-mail]
Subject: portable antenna for NVIS?
To: [e-mail]

In article <2pceka$[e-mail]>, [e-mail] (Donald E
Rickerson) writes:

>I am looking for aportable antenna to use with a Near Vertical Incident
>Skywave antenna that works with a adaptive HF radio, ALE.  It has to be
>a broadband antenna that can be erected by semi-skilled operators.

>I have looked at the inverted V and the sloping dipole, but they are long
>at the 50 plus degree take-off angle needed for NVIS at the 2-7 Mhz
>range.

Maybe i'm missing something, but:  what does the length of the antenna have to
do with NVIS excitation per se?
Other NVIS systems I'm familiar with have used low (30-50') fan dipoles of
about 50' length.  Making the dipole into a fan shape (i.e., several conductors
per "leg", spread out over about a 20-30 degree angle instead of a single wire)
broadens the frequency response of the antenna considerably.  Mounting it less
than 1/2 wavelength above ground at the highest frequency guarantees that the
majority of the radiation will be at elevation angles >45 degrees due to the
ground reflection.

Other systems use antennas actually mounted on the surface of the earth (Eyring
Industries in Utah sells such a system).

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

Date: 25 Apr 94 14:16:43 GMT
From: [e-mail]
Subject: Transceivers in modern cars
To: [e-mail]

Hi everybody,

I 've recently seen a message about the problems that a radio can create in a
modern car computerized ignition and injection system. The person asking was
interested in a Honda Accord '89 (sorry, I do not have the name right now, as
a mysterious function of the mail program erased the ... "erased files
folder").

Althought I do not have exactly a HONDA Accord, I have been using verious
transceivers in my HONDA Civic '92, with absolutely no problems. Let me
describe the setup, for anyone interested.

At the top part of the rear hatch door, the Civic has a small spoiler. This
spoiler received the antenna mount, and from there a 5m pre-fabricated cable
(from Diamond, sorry no part number now, but if someone is interested I can
find it) connects the antenna mount with the transceiver. Until today, I 've
used the following rigs, in that car : A Kenwood TM-732, a Kenwood TS-450SAT
and a Icom W2 with a Microset 50 Watts linear amplifier (this is the rig most
often used in this car). The antennas used were all from Diamond, that is a
NR-77 (a 40 cm dual band antenna), a very similar antenna (again no part no) on
ly a bit longer, about 1 m total length, and for HF a 7 MHz antenna (which is
used only when the car is stationary, as it is quite heavy for the spoiler).

I've used this equipment with up to 50 watts for the 2m/70cm rigs and up to
100 watts for the HF, with absolutely NO PROBLEM to the car computer.
Actually, I was also a bit worried in the beginning, as the Civic has the
computer, under the passenger's feet, which is very near to where the rigs
were mounted, but it seems that it is either very well shielded or insensitive
to RF.

Oh ,yes, the local distributor of Honda, send a fax to the Japanese headquarter
s for instructions, but -guess what- they didn't have any information on the
topic.

Again, I apologize if this message is somewhat vague, as far as part numbers
are concerned, but it was written at the office and my RAM doesn't store these
things well (parity errors or age symptoms).



Best 73 de SV1CEC

John Caradimas

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End of Ham-Ant Digest V94 #119
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