[BC] Part 15 radio station

[Tom]

Richard - to be Part 15 compliant, only ONE turn would be allowed in a 
three-meter-circumference loop. 

Helical antennas can be argued that the "antenna" is actually one huge 
momma coil....

Has anyone else with maybe access to NEC-4 tried the ground-mounted 108" 
whip / TX on a real 120-radial quarter-wave ground, and spaced near - 
but not on or obviously affiliated with - a quarter-to-half wave tower?

I'd like confirmation one way or the other that this works..... because 
it would be a HUGE loophole if it does... or even if it just works with 
the ground, whether there's a tower nearby or not....

RichardBJohnson at comcast.net wrote:
> Actually double digits. And I am sure that a 3 meter loop will
> be more efficient than a 3 meter whip at broadcast frequencies.
> Furthermore, you get to adjust your input impedance, getting
> it out of the lossy mud of a tiny vertical, where most of your
> power goes into heating up the mud.
>
> I have made 60 kHz loops for receiving NIST and They were quite
> efficient, having an aperture about 40 times their size. The NIST
> transmitter is in 50kW in Colorado. There is no skywave so what
> you get follows the earth's curvature and is very weak on the East
> coast. 
>
> Something like these would work just fine.
>
> http://www.frontiernet.net/~jadale/My%20Loop%20Antennas.htm
>
> Basically, you wind enough wire around your frame until you can
> resonate it with a small trimmer capacitor, the smaller the better.
> Ideally, self-resonance. Then you add a turn, not connected to
> anything but a coax connector, or in your case a transmitter. If
> the impedance is too low, you add another turn, etc.
>
> These things can give crap radios uV/M sensitivity. A 60 kHz
> one made out of 50-pair cable, resonated to 60 kHz provides
> enough signal to feed a CMOS logic gate directly for the frequency
> standard I designed.  
>
> --
> Cheers,
> Richard B. Johnson
> Read about my book
> http://www.LymanSchool.org
>
>
>  -------------- Original message ----------------------
> From: Cowboy <curt at spam-o-matic.net>
>   
>> On Friday 16 May 2008 05:29 pm, Dana Puopolo wrote:
>>     
>>>  They'd probably use the total length if the loop.
>>>       
>>>  From: RichardBJohnson at comcast.net
>>>  
>>>  May I suggest a loop antenna? Something that is the allowed height,
>>>  but square, should produce a reasonable field on-edge, with
>>>  practically nothing at 90 degrees.
>>>       
>>  You'd find that the efficiency of a small loop for transmitting
>>  is on the order of percent in single digits.
>>
>> -- 
>> Cowboy
>>
>>     
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-- 
Tom Spencer
PG-18-25453 (nee' P1-18-48841)
http://radioxtz.com/
Part 15 transmitters on AM 640 and FM 100.1