[BC] Detroit 1500

[RichardBJohnson at comcast.net]

Just more variables in a computer program. If the math is correct
(doesn't use any fudge-factors), and the mutuals are correctly
handled, an 'N' tower array can be figured.

When I worked for General Electric's Advanced Development
Group in Rancho Cordova, CA., we invented phased-array
ultrasound. It uses directional antenna theory and typically
uses 64 "antennas" (transducers). We developed the
computer programs using directional antenna methods
except we steer a lobe, not a null. Also, we need to suppress
side-lobes so there is a correction window in with which
we convolve the array factors. Each of those antennas
have all the bothersome characteristics of their electrical
counterparts, including mutual impedances. The
frequencies run from 2.7 to 10 MHz. The only difference
is the velocity. It's the velocity of sound in water, about
1497 m/s at 25 °C, instead of the velocity of RF in air.
 

--
Cheers,
Richard B. Johnson
Read about my book
http://www.LymanSchool.org


 -------------- Original message ----------------------
From: Barry Mishkind <barry at oldradio.com>
> I always get this one confused, but it was either 1500 or 1440 that 
> tried a 21 tower application.
> 
> It would be nice to have the definitive story here, but I do not 
> recall any other application above, what?, 12 or 14 towers?
> 
> The physics of 21 towers (spacing, etc), not to mention the cost in 
> land and steel, would make it a rather unworkable project at all 
> today, one would think.
> 
> At 10:21 AM 10/30/2007, Dana  Puopolo wrote
> >Yep.
> >
> >1500 in Detroit is the most obvious example. They used to have 12 towers and 5
> >kW at night. Now they have 9 towers and 10 kW.
> >
> >WNLC now has zero towers and no power day or night.
> 
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