Subj: Re: TopBand: Heard Island Update
Hi Glenn!
I'm copying this to the reflector since I think others might
also be interested in your response to my questions.
1. What is a "Gladiator" vertical for 160? I certainly hope it
is not another Gap or Butternut. Is it reasonably large electrically
and can it stand the ice loading and winds you must expect to encounter?
I personally question the wisdom of trying to maintain four of whatever
it is in the severe environment of Heard Island. I would rather have
one really good and mechanically rugged vertical like the BC Special.
I also would prefer one good vertical on transmit for the simple reason
that you may experience unexpected propagation modes and directions.
This is especially true at Grayline which you mentioned in your announcement.
The Gladiator Verticals are made by R Myers Communications
of Phoenix, AZ. See: http://www/primenet.com/~bmyers/
The Gladiator Verticals are center-loaded and have a very high Q.
They are *very* rugged and stout. One person can put it up, even
in a stiff breeze. I've done it many times. It is *very* easy to
assemble, especially since I have them all pre-marked. Even
though probably not needed I have placed a guy-point about 2/3
the way up. We are pessimistic about the integrity of all of
our antennas with 100+ mph winds 2-3 times/week. Even the
beefed-up Battle Creek Special might not be sturdy enough
(would you then call that a "roasted" beefed-up BC Special?).
The capacitance-capped vertical by ON4UN also might not be
sturdy enough.
I am not overly concerned with the "complexity" of the
4-SQ array as some have mentioned. Each of the verticals is
*easy* to assemble and mount. A single coax and control cable are
pre-made to run to the phasing box and a single RG-11 line runs to
each of the 4 verticals. They are all partially pre-assembled,
pre-marked and each 4-SQ array comes in it's own crate. If the
Gladiator Verticals were similar to the Battle Creek Special,
forget it! I am NOT knocking the BC Spl, but we are talking about
simple survivability.
I personally put together the five 4-square arrays we are
taking to Heard. I had the 160M 4-SQ up for only a couple of
days and it equaled my high dipole at 140'. (Since then I've put
up a full size 1/4-wave vertical, but the Heard antennas were
shipped in early August.) There was 20-25 dB F/B and during the two
thunder-stormy days it was up, it was easy to work both coasts,
again, as easy as with the high dipole. (It might not sound like
much, but the noise level was 40-50 dB over S9.)
I had the 80M 4-SQ (Gladiator Verticals) up for a week
and compared it to my full-size 1/4-wave elevated radial 4-SQ
made from Rohn 25. In nearly every case the Gladiator Vertical
4-SQ *equaled* the performance of the full-size array. It was
never better, and only two stations reported slightly weaker
signals from the Gladiator Vertical array. That should be
encouraging!
The two 40M and one 30M 4-SQ arrays are full-size and
should represent no compromises. Even these verticals are guyed
for the wind. These should "keep on playing" long after the 40M
beams have blown away.
Even if some of the verticals are blown down, we will still
have "single" verticals to use, on any of the bands above.
2. How many Beverages do you plan to put up? I expect that you
will experience a brief opening to the Pacific Northwest at your sunset
(in a SE direction) at the same time as middle and eastern Europe (to the
NW). If you don't have Beverages in the right directions, you may actually
be better off listening on the transmit antenna, especially given that you
will have NO manmade noise (except your own of course!) I'm going to give
this some more thought and suggest some directions for your Beverages.
Europe, East Coast and Japan will most likely be straightforward short path,
but some of the other areas may need some forethought. This is another case
where an omnidirectional receive antenna may be a nice supplement to Beverages.
We have enough wire and matching units to put up 5-6 1000'
Beverages in about any direction. Your suggestions would
certainly be appreciated!
Experience with my 4-SQ arrays here in MN, is that
basically everything heard on a Beverage can be heard on the 4-SQ.
The F/B ratio reduced a lot of noise and helps to hear.
Even if we can't get "full-size" Beverages up, *any* Beverage is
better than *no* Beverage in my book.
3. While I certainly applaud the 160 ambitions of the expedition, I am
also reminded of the weather problems the South Sandwich group encountered,
as well as the KISS principle (Keep It Simple Stupid) and Murphy's Law.
It is more important to most of us on Topband that you have a decent signal
on the band available 100% of the time, than a colossal signal that is
only intermittently available due to weather or complexity-induced outages.
Please take my comments in the constructive manner they are intended and
I'm looking forward to hearing your response.
Thanks for the reminder. All of our antennas will be
"environmentally challenged," as an understatement. (So will the
Hearders, as you call us!)
As stated in our TopBand announcement, if it is dark on
Heard, WE WILL BE ON 160M! Of that, you can be assured. I'm sure
we will seriously consider working North America, say listening on
3805 or whatever...... We will be doing our best to work the
grayline. We will be finalizing the operating plan very soon and
the Heard team will work this out...you can be assured.
73, Bill W0ZV
P.S. BTW, I remember seeing a picture of "Big Ben" on Heard and I recall it
looked like it was covered by ice. Since you are from Minnesota, I am sure
you are well aware of the mechanical and electrical problems caused by ice
loading. You may need to explain this to some of the less "ice challenged"
team members from the warmer climates!
Bill, we had ten days of -50F or colder on the thermometer
this past winter. (Record on 1 Feb 96 was -61F!!! which matched
the state's all time record.) That is why I joined the Heard
team...so I could be in summer in January & February! hi hi
73! Glenn
_________________________________________________________________________
Glenn R. Johnson, M.D. email: grjohnson@vax1.bemidji.msus.edu
Home: 218-243-2611 BBS: WA0PUJ@K0LAL.#NCMN.MN.USA.NA
FAX: 218-243-2918 Cluster: WA0PUJ@WA0PUJ (PacketCluster)
Work: 218-759-5000
"Orthopedic Surgeons
WA0PUJ, VO2GJ, VP2EZ, VP5H, ZF2RT get all the breaks!"
Soon to be: FR/WA0PUJ & VK0IR op
Homepage: http://vax1.bemidji.msus.edu/~grjohnson/homepage.html
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