The B&W "folded dipole" antenna is the well known "terminated folded
dipole" design and it has significant, documented losses - as much as
6dB or more on many bands.
The B&W dipole is a bad idea for amateur service where signal levels
are limited by regulations limiting transmitter output power. Other
licensed services have the option to increase transmitter output to
compensate for losses in the antenna system - no so for amateurs.
The B&W and (other swamped antenna designs) are nothing more than
snake oil - like the "automatic tuner" in the late 70's that was
nothing more than a resistor in some potting material.
73,
... Joe, W4TV
On 4/21/2011 1:30 PM, Fred Serota wrote:
> Suggest trying Barker and Willamson's folded dipole. They have three or 4
> varieties, some made of stainless wire for very tough climates. The longest
> is approximately 120' and fives a flat SWR under 2:1 for 160-6 meters. Due
> to built in matching does not need a tuner. This antenna has a special name,
> I have forgotten. Can be ordered direct or I, thing, through HRO and AES.
>
> Mine is hung as an inverted V and works out very well.
>
> Fred, K3BHX
>
> --------------------------------------------------
> From: "Jim Brown"<jim@audiosystemsgroup.com>
> Sent: Thursday, April 21, 2011 1:24 PM
> To:<towertalk@contesting.com>
> Subject: Re: [TowerTalk] Multi-band dipoles
>
>> On 4/21/2011 9:22 AM, Tom Osborne wrote:
>>> Are 15 and 17 too close together to have 2 antennas on the same feedline.
>>>
>>
>> I think so. I had the same problem with 40, 30, and 20 in a fan -- the
>> 30 was too close in length. From my experience, an 80/40 fan loads and
>> works very will on 15M and 17M, with the expected lobing from any
>> antenna that is much longer than a half wave. Before I had my SteppIR, I
>> ran 30M, 17M, and 12M on my 80/40 fans and was very happy with them. I
>> still use them on 30M, and have 100 countries confirmed on that band.
>>
>> 73, Jim
>>
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|