[Antennas] B&W AC 1.8-30 vs BWD terminated antennas?

Sun Sep 5 23:50:34 EDT 2004

A friend of mine who is very active in the club and even more interested in
antennas than I (That's saying a lot!) received one of the t2fd antennas
from a ham that thought it sucked. He has been studying the antenna and
testing it now for about three months. We have discussed it extensively on
the air. Here are the conclusions I get from it.
The B/W antenna is not exactly the same specs as the original. It is a
"tilted" dipole and in order to get the proper performance from it, it needs
to be tilted at the correct angle as in the instructions.
When properly installed and carefully compared to a slanted dipole, the T2FD
works almost exactly the same as the dipoles except for two bands, I forget
if it were the longer two bands or the shorter two. I think it is a little
lossy on the bands that are longer than the antenna. Regardless, it was
still effective even then. 
The previous owner hung the antenna up like a dipole and had nothing to
compare it to but his beam. 
You can find more information on the internet about the antenna. It's
proper name is the Terminated Tilted Folded Dipole and is most commonly
referred to as the T2FD or TTFD. The reviews I read on the internet are
mixed. There are plenty of folk who really don't like the antenna and
plenty that praise it. 
Remember it's purpose and your purpose for having it. It was made to setup
quickly and easily and to work instantly. If you are working DX primarily,
it may not be suitable, but if you can only have one antenna and it fits
your real estate, then you may have a real winner there. 
Wishing you the best.
N4PGW
73 for now
Buck
-----Original Message-----
From: Phil Florig [mailto:W9IXX at arrl.net] 
Sent: Sunday, September 05, 2004 9:54 PM
To: Antenna Reflector
Subject: Re: [Antennas] B&W AC 1.8-30 vs BWD terminated antennas?
Hi guys,
Thought might make a few comments to maybe clear a few things.
1. The resistor that is in the B&W antenna is not at the feed point,
it is at the end where the two folded wires return to the center area.
2. I would also be interested in hearing an answer to Jays' question
but have not seen yet.
3. Was mentioned below that the antenna is less effective than a dipole
and is not intended for DX work.
4. The prime advantage to the antenna is that it can be instantly switched
to ANY frequency and still have a less that 2:1 swr. This ant is used on
ALL frequencies in the range of 3-30MHZ. In MARS and Gov. services we use
ALE which switches in the millisec range and therefor don't have time
to use a tuner either auto or manual.
5. I have up a 170ft B&W unit and it does not compare to the inverted V's
but I know that and don't rely on it for ham work. Sure is a nice idea
though if you want to change freq rapidly w/o tuning. Be the first there
when a new spot comes up...... HI......
6. I know some have done research on the ant and LB Cebik has an article
on this type of antenna. As long as I have this antenna up and working
if anyone wants any info or testing information I will try to help with
tests if I can. Have limited equipment and antenna knowledge and that's
why I think this reflector is great. I have learned a lot here and
appreciate
all the input. Keep up the good conversation.
73 Phil W9IXX/AAM4ENC/AAR4XX
PS: Usual disclaimers apply if required...
At 20:36 9/4/2004, you wrote:
>Has anyone run an efficiency comparison between the Barker and Williamson
>BWD ninety-foot terminated folded dipole or "T2FD" antenna, versus their
>similar AC 1.8-30 terminated end-fed vee?
>>A few thoughts:
>I am guessing that the vee encloses more space and could be more efficient
>in that regard.
>Both antennas use similar baluns and load resistors.
>Both are loops if you consider the counterpoise wire in the AC 1.8-30 going
>from one leg of the balun to one leg of the resistor.
>>I'm aware that these antennas are a few DB less efficient in the 2 and 4
MHz
>bands than
>a resonant wire- but my application is instant frequency change, NVIS and
>not QRP or DX.
>>Thanks,
>Jay
>AAR9QM/W6CJ
>>>>- - -
>>Your moderator for this list is:
>Larry Wilson KE1HZ antennas-owner at mailman.qth.net
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-----------------------------------------------
Philip Florig e-mail:pflorig at ieee.org
115 Horne Rd. (or):W9IXX at arrl.net
Columbus, NC. 28722 amateur radio:W9IXX
USA also:C6AXX-J3X-T30,31,32,33P-VP2MPF
 team member:AH1A-C6DX-J3A-VP2MX
 MARS:AAM4ENC/AAR4XX
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11651 Mayfield Ave. fax: 1-708-385-7515
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Your moderator for this list is:
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