Sorry ... I don't buy that.
1. It can ONLY be quieter because of additional loss. There is no
other reason for it to be quieter since it has the same polarity and
pattern as an equal length dipole.
2. Without actually running a model, it would seem that any frequency
that results in a current maximum at the resistor would have a lot of
loss irrespective of what the SWR would be without the resistor.
Dave AB7E
On 4/21/2011 7:31 PM, K3WRY@aol.com wrote:
> All interested hams:
>
> With many opinions about the B& W folded dipoles, one needs to understand
> the design and actual tested operations of this antenna design.
> It actually is quieter on receive, and the loss is only higher when the SWR
> rises regardless any band or frequency operation.
> Therefore, if the SWR is kept low, the transmitter efficiency of the
> antenna is actually measured, the actual radiated power can be very high with
> minimal power being actually lost through the resistor.
> The higher the SWR, the less efficient the antenna and consequently more
> power is lost through the resistor.
>
> Regards,
> Dr Joe Palsa
> k3wry
>
>
> No trees were destroyed in the sending of this message, however, a
> significant number of electrons were terribly inconvenienced
>
>
> In a message dated 4/21/2011 4:39:50 P.M. Eastern Daylight Time,
> steve@karinya.net writes:
>
> 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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>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>> _______________________________________________
>>
>>
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