The military love them because they value frequency agility over efficiency.
Cebik's analysis put the power in the terminating resistor at somewhere
between half and 90% of the applied power, depending on the band.
73,
Steve G3TXQ
On 21/04/2011 21:30, Grant Saviers wrote:
> I had one of these elevated resistors briefly in 1980. It was very very
> quiet at both ends.
>
> Might be ok for quick GOTA, emergency, or NVIS, that's what it seems the
> military wanted it for.
>
> Grant KZ1W
>
> On 4/21/2011 12:36 PM, David Gilbert wrote:
>> By all accounts I've read, the B&W folded dipole is indeed broadband.
>> Since it has a relatively small fixed "tuning network", that can only
>> mean it has significant loss relative to a normal dipole. Estimates
>> I've read vary between one and two S-units.
>>
>> By all accounts I've read, it is a "quiet" antenna on receive. Since
>> noise rejection can only come from pattern or polarity discrimination
>> and the B&W antenna has no more of either of those than does a standard
>> dipole, that again means it has significant loss. The antenna is
>> probably just as quiet on the other end as it is on yours.
>>
>> Dave AB7E
>>
>>
>>
>>> From: "Fred Serota"<fserota@msn.com>
>>> Sent: Thursday, April 21, 2011 1:30 PM
>>> To:<jim@audiosystemsgroup.com>;<towertalk@contesting.com>
>>> Subject: Re: [TowerTalk] Multi-band dipoles
>>>
>>>> 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
>> _______________________________________________
>>
>>
>>
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