Tom-
This might sound sarcastic, but I mean it literally-- You are Too Kind.
I actually saw someone (on AntenneX) defending the CFA as a new idea this
week!
I'm afraid "Dumb Down" is a fact of current life. Why can't the publication
you referenced afford ( and support) a real Technical Editor?
At 10:55 PM 7/21/2005 -0400, Tom Rauch wrote:
> > At 02:44 PM 7/21/2005, SavageBR@aol.com wrote:
> > >BTW we're not dumbing down TowerTalk.
>
> > >Indirectly Tower Talk and any other technical reflector
>is being dumbed
> > >down. Or, the need is being eliminated. As the
>technically competent,
> > >experienced, capable amateur dies off, so will the real
>hobby of
> > >amateur radio.
>
> > To relate it more to antennas.. I think that amateurs are,
>in general, much
> > more sophisticated when it comes to antennas these days.
>Compare the
> > antenna projects in ARRL handbooks over the years. Some
>are perennial
> > evergreens, but modern directive antennas are far better
>than what was
> > "state of the art" in 1960 or 1970.
>
>I almost hate to post this, but I seriously question the
>direction our technical resources are heading.
>I think peer review processes are slipping. Let me give an
>example.
>
>August QST, page 35, has a very well written four page
>antenna construction article. It unfortunately has a very
>simple basic point wrong. The authors based the construction
>on the incorrect assumption a small horizontal loop antenna
>radiates a vertically polarized omni-directional signal. Of
>course it doesn't have vertical polarization. It radiates an
>omni-directional horizontally polarized signal!
>
>The article claims a comparison was made between the loop
>and a J-pole. It said signals were "even". That can't be
>true in line-of-sight communications unless the J-pole had
>some very serious flaws or an esoteric effect like feedline
>radiation or metallic structures nearby was affecting
>antenna patterns.
>
>If you read the editor's note on page 35 it says: "While
>horizontal loops do better in noisy situations because that
>local noise tends to be mainly E-field oriented ....". What
>does that mean? What is "mainly E-field oriented"?
>
>Now here's the real sad part. The antenna isn't good for the
>original intent...efficient omni-directional vertically
>polarized communications.....no matter how we position the
>loop. Turn the loop on edge and it has a bi-directional
>vertically polarized signal while wasting half of the
>applied power as straight-up-and-down horizontally polarized
>radiation. Lay it down flat and it is omni-directional, but
>unfortunately it is also horizontally polarized.
>
>Articles like this embarrass and discourage everyone from
>the authors to the editor to the poor fellow trying to learn
>how to build something. They should be edited and corrected
>before publication, not after.
>
>Now if you roll over to Technical Correspondence on page 60,
>you find an opening letter about Packet, Pactor, and NVIS.
>The letter writer wastes no time in being critical of an
>older Elmer (he actually used those words) who thought the
>idea of an 18 inch high dipole antenna for 80 or 40 was a
>dumb idea.
>
>The writer uses some fantasy technorubbish about groundwave
>and NVIS being "out of phase" and the 18 inch high antenna
>curing a "phase distortion" problem.
>
>Well, I'm in full agreement with the older Elmer. The only
>thing that happens when a horizontal dipole antenna is
>installed significantly lower than 1/4 wl is the efficiency
>drops, often like a rock!
>
>Thirty years ago people knew if we wanted a dynamite NVIS
>signal we installed a dipole at 1/8 to 1/4 wl high and laid
>a screen or grid of wires below the antenna to reduce earth
>losses. Now we have people proclaiming in the best interests
>of "Homeland Security" communications we need to use what
>really amounts to a 10 dB or more attenuator on a 5 to 10
>watt transmitter... rather than building a good system.
>
>This is probably why, when I listen to the GA ARES net, a
>significant number of stations can't hear each other. Yet
>with a dipole 35 feet high over a large ground screen I can
>hear and work all the dog-gnat signals coming from grossly
>inefficient antennas that are (no surprise) quiet. This is
>where we are headed.
>
>How do we educate people and build reliable communications
>networks when many technical concepts making it into what
>once was our only peer reviewed reliable source of
>information are getting so ridiculous?
>
>The CB'er down the road has metal pie pans with holes in the
>center strung on his coax to "divert lightning" and an old
>water cooler jug filled with pennies and saltwater for a
>station ground. I fully expect to see that idea published
>someday in a radio communication system handbook. After
>all, steel wool baluns made it in, and we now have 18 inch
>high dipoles that cancel phase distortion and horizontal
>loops that radiate a vertically polarized omni-directional
>signal. Pie pans seem the next logical progression.
>
>73 Tom
>
>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>any questions and ask for Sherman, W2FLA.
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
Bill Aycock - W4BSG
Woodville, Alabama
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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