EDIT: change the second paragraph to:
Included are results reported by the USN, who did the design, in multiple
comparisons
to existing antennas at many locations as well as detailed construction
details. Wire spacing and resistor value combined with feedline impedance is
critical. The tilt angle is less critical and can be 20-40 degrees.
Carl
KM1H
----- Original Message -----
From: "ZR" <zr@jeremy.mv.com>
To: "Herb Schoenbohm" <herbs@vitelcom.net>; <topband@contesting.com>
Sent: Friday, August 03, 2012 12:27 PM
Subject: Re: Topband: Antennas
> The T2FD was described in QST for June 1949 and CQ for November 1951 and
> February 1953, all by USN Capt G.L. Countryman, W3HH.
>
> Included are results reported by the USN, who did the design, in
> comparison
> to existing antennas as well as detailed construction details. Wire
> spacing
> and tilt angle are critical.
>
> Ive had one up for several years primarily as a SWL antenna for a couple
> of
> boatanchor receivers using a 10W resistor and have also made numerous
> 10-40W
> contacts with it without difficulty 80-17M. Ive no comparison wire
> antennas
> at similar heights so no performance claims are being made other than that
> I
> can work DX and domestic stations with it.
>
> The so called T2FD's sold these days by the usual ham dealer suspects is
> nowhere near the original design so its no stretch as to why its not a
> great
> performer.
>
> Others just give it a thumbs down without ever trying it and just waste a
> lot of others time with their views.
>
> Carl
> KM1H
>
>
>
> ----- Original Message -----
> From: "Herb Schoenbohm" <herbs@vitelcom.net>
> To: <topband@contesting.com>
> Sent: Friday, August 03, 2012 11:29 AM
> Subject: Re: Topband: Antennas
>
>
>> Price, The Military and U.S. Embassies use T2FD type of antennas all
>> over their deployment perhaps due to the fact that they do work as long
>> as you have plenty of horsepower to feed them with. I think the
>> requirement of frequency agility for their requirement outweighs the
>> inherent inefficiency. If you don't mind putting a "radiating dummy
>> load" in the air then perhaps it is not such a bad idea. The design is
>> still part of the military nomenclature with an ANN number and their is
>> one on the VI national Guard building a few blocks from my office. It
>> is hooked to a 10KW Harris 2-30 Mhz box to connect to FEMA Region 2 on a
>> multitude of frequencies driving by the propagation at the moment. The
>> T2FD mil spec version is supposed to be rugged enough to work through
>> and survive a Cat 4 hurricane. None of my antennas nor towers could make
>> that claim.
>>
>>
>> Herb Schoenbohm, KV4FZ
>>
>>
>>
>> On 8/3/2012 10:21 AM, HAROLD SMITH JR wrote:
>>> Hi Tom,
>>>
>>> I am suprised that no one has brought up the "T2FD" antenna and
>>> of course the B&W "All-Band" antenna.
>>>
>>> It was in one of the magazines back in the (50s?).
>>>
>>> 73
>>> Price W0RI
>>> _______________________________________________
>>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>>
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>>
>>
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>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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