Hi Jay!
I like that system! I have constructed and have had up since 1992
a pair of stacked logs that cover 13.5 to 30 MHz, at 55 and 110 ft.
Each log is 18 E on a 62' boom, top rotated with a large PP and
bottom rotated with a pair of TIC ring rotators separated by 8 ft to
get vertical stability. Electrical phasing is frequency independent
and I do the top-bot-in-out phasing with a pair of baluns, two
matching transformers, and a three relays. I'd like to compare notes
sometime. The antenna is a winner, beating my stacked yagi
systems by a bit. Let me know when you get that on the air! I'd
like to hear it! ( The yagis suffer from nearby interaction with other antennas
that the logs aren't as sensitive to, modeling shows this as well)
It looks as if the bottom two logs are identical. What is their freq range
and what is the range of the top log? It looks like the top has the same
high freq limit but goes X/2 lower than the bottom two. (scaling the pics)
73,
Chuck..K1KW
-----Original Message-----
From: Jay Terleski [SMTP:jayt@arraysolutions.com]
Sent: Sunday, July 29, 2001 9:55 PM
To: K4tmc@aol.com; towertalk@contesting.com
Subject: Re: [TowerTalk] Awesome HF Array Spotted
Hello TTers and Henry,
The Antenna system has been going up for 3 weeks now, and we are finally
finished. I hope to have time to get on the ham bands with it with the call
of K4A. But time is not on our side since there are 2 other towers to attend
too.
The system is 3 logs top one at 122 feet. Mid at 80, and lower at 40.
Phased in any combination of course, and we can take the top one out 180
degrees of phase for higher angles.
We also installed NVIS antennas which are dipoles fed with a 600 ohm
ladderline, and we put up 4 900 ft longwires on tall poles, which are
playing very well for the missions these guys have in Africa.
The system was put up by Paul, K7PN Custom Metal Works, and myself as Array
Solutions. Array is the prime contractor.
We are looking forward to getting an article in QST. The Special Forces
seem very willing to let us discuss most of the system details. They are
most impressed. The Ft Bragg area is interesting, we get a daily air show
from Pope AFB. A10s, C17s, C5s, and other monster aircraft fly over our
heads all the time. alot of helicopters too. We lit the tower with a twin
obstruction light to keep em at a safe distance. 8o}
Jay
----- Original Message -----
From: <K4tmc@aol.com>
To: <towertalk@contesting.com>
Sent: Friday, July 27, 2001 9:11 PM
Subject: [TowerTalk] Awesome HF Array Spotted
>
> On the way back from a week-long business trip, I made a side visit to a
> surplus outlet in the Ft. Bragg, NC area this afternoon and spotted a new
> tower near the base. What at first I took to be another cookie-cutter
cell
> tower turned out to be something else. As I got closer there seemed to be
> some large horizontal attachments to this one. As I drove closer it was
> evident that these were HF log-periodic arrays. And, there were 3 of them
> stacked on this one tower! My first thought was that this was not a
military
> setup, since they usually only have one LP per tower; so maybe this was
some
> ham operator who had won the lottery and had put up a "dream station".
Since
> there were some people still working in the field around the tower base, I
> slowed and pulled into the driveway. As I walked across the field toward
> what appeared to be the construction tent, out walked Jay Terleski, WX0B!
It
> seems that Array Solutions and Custom Metalworks (Paul Nyland, K7PN) have
> teamed-up to install this system for the Army Special Forces. They have
> spent the last 3 weeks working on the installation.
>
> Luckily, I had my digital camera along, so I have placed two pictures at
the
> following web site www.geocities.com/k4tmc/wx0b-22.jpg and
> www.geocities.com/k4tmc/wx0b-31.jpg . Here is a quick description: 170
ft.
> Rohn 65 tower with 3 custom Tennadyne log periodics. They have also
> installed three 900 ft. terminated longwires aimed at various foreign
> locations. Jay indicated that he is planning an article for QST on this
> installation, and he will have pictures at the Array Solutions web site
later.
>
> Also, Jay may be on the air with this system over the weekend. He has
> obtained permission to use the call K4A. So, look for him with a huge
signal
> anywhere on 40 to 10 meters.
>
> 73,
> Henry Pollock - K4TMC
> Raleigh, NC
>
>
> -----
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> Problems: owner-towertalk@contesting.com
>
>
-----
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-----
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