ST-2 Scantenna Surprising Test Results

digitalanalog

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May 18, 2007
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I took the matching transformer off the end of the antenna (factory location) and moved it to the Center of the
antenna and before I reattached it, I removed the aluminum connecting rods that tie the front,center and end together.
so you now have a ST-2 with a matching transformer mounted in the center on the two long radials and NOT tied into the front
800-900MHz section at the front.

Results:
25-170MHz(aprox) - Hit and miss, some better some way worse, but mostly worse all around.
170-200MHz (aprox) - Better performance, but nothing to great.
200-400MHz.(aprox) - BIG BIG IMPROVEMENT, db measurments doubled and SWR dropped way down..
400-550MHz(aprox) - Much better both SWR and db. I say at least a 15-20% improvement.
550-1000MHz (aprox) - Results were surprisingly about the same. (was amazed the 800-1000MHz did not get any better or worse).

Your results may vary, but this was a very interesting test.

This is truly an amazing antenna, doing simple things to it can make BIG changes.
I also tested this antenna with the WINGS removed, That was interesting as well
I now know what the wings do and where they work as far as band coverage, again I was amazed.

Although not adveretised as such, but as many know, this is a Milair Antenna and
by making a few SIMPLE changes it becomes a Very Good 200-400MHz antenna.

No pieces where injured or harmed in this testing.
and no pieces have been Shortened or Lengthened.
 

Ubbe

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Sep 8, 2006
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Stockholm, Sweden
That single antenna should be more or less a 75 ohm antenna and that 300 to 75 ohm transformer reduces the signal level up to 4 times. It would be interesting to use a 1:1 balun on it. Perhaps an indication can be had if you connect the coax directly to the antenna and then coil up the coax 3-6 turns as close as possible to the antenna.

That front dipole with a second pair of dipoles riveted to it that can be folded down equals in lenghts to 450MHz and 510MHz 1/2 wave dipoles, so shouldn't have any impact in the 700-900MHz range. That center antenna are so big that it overshadows any signals from other antennas connected in parallell and should work more effeciently when used alone without anything else hampering it.

They say that it is some antenna guru that have designed TV antennas that designed the ST-2, but that is like having a car designer to design a bicycle that should be suitable for both gravel and tarmac. He can't use any of his knowledge and experiance to design a bicycle that works sucessfully.

/Ubbe
 

spacellamaman

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municipality of great state of insanity
great scott! 102 inches! never noticed that before. i'll take 3!

oh yeah....hmmmm....discontinued....like a decade ago....

hmmmm guess i need to start getting buddy buddy with some of you guys so maybe i can get it in your will that "and i authorize my executor to dispose of my ST-2 to the handsome and intelligent gent spacellamaman"
 

RFI-EMI-GUY

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Dec 22, 2013
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great scott! 102 inches! never noticed that before. i'll take 3!

oh yeah....hmmmm....discontinued....like a decade ago....

hmmmm guess i need to start getting buddy buddy with some of you guys so maybe i can get it in your will that "and i authorize my executor to dispose of my ST-2 to the handsome and intelligent gent spacellamaman"
Maybe some enterprising person will document the dimensions of all the elements and the geometry of this beast so that a DIY project could be made. It was so reasonably priced , a shame it is no longer available.
 

TailGator911

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Fairborn, OH
I had one - the Grove version - and I lost it in a 2004 hurricane at the Florida house. Great antenna. If someone were to resurrect this antenna I would definitely buy one in a minute.
 

LesWurk

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Dec 17, 2009
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Land of RF
has been done



Maybe some enterprising person will document the dimensions of all the elements and the geometry of this beast so that a DIY project could be made. It was so reasonably priced , a shame it is no longer available.
 

RFI-EMI-GUY

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iMONITOR

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If it was patented I wounder if it's run out? Surprised someone didn't buy the rights and start manufacturing them again. Make it stand up to rough weather and it would be a big hit!
 

iMONITOR

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Even if I leave my phone at home they can still track me. My new Ford Edge has a GPS location transmitter that I can't find a way to turn off.
 

iMONITOR

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Lowes sells wire cutters
LOL! This Edge has so much hi-tech BS on it, seven computers! If I cut a wire or disable anything it will probably cost thousands to get it running again if ever! :rolleyes:
 
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