[BC] Dallas' 1190

[DHultsman5 at aol.com]

In a message dated 10/30/2007 11:52:13 AM Central Daylight Time, 
peterh5322 at rattlebrain.com writes:

> 
> >What I foind interesting is that the major lobe of that 12 tower 
> site appears
> >to be broadside from the array, with a large minor lobe coming off the
> >"bottom".
> 
> On such an array, the pattern maximum is always "normal" (i.e. 90
> degrees) to the axis of the larger of the two spacing units.
> 
> The back-side suppression is always effected on the axis of the smaller
> of the two spacing units.
> 
> The minor lobe towards the SE is a consequence of asymmetrically driving
> the elements of the array, IOW, this array is not a strict
> "multiplication method" array, where the six-tower broadside sub-array is
> multiplied by the two-tower sub-array.
> 
> 
> >It still amazes me how patterns like this can be "manufactured" with
> >such
> >precision these days. The wonders of computer technology and GOOD 
> Consultants
> >to oversee the build and tune-up!
> 
> 

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Peter is correct as usual,  The 1190 kHz. nightime site for KLIF was one of 
the early "computer designed patterns"   Ralph Dippell and Richard Biby were 
the principal designers the array was modeled on a time share computer located 
in Cleveland in the late '60's.   

It was tuned up using same old technology.   I tried to get them to install a 
TWX machine with access to the main-frame in Cleveland at noght direct from 
the site. I believe we could have decreased alot of telephone and office time 
charges with the data entry at the transmitter site and the receiving the 
download information.

Today technology for tuning is so neat compared to the olden days.   Some of 
the tools as demonstrated by Ron Rackley at Barry's Radio Guide DA seminair in 
Orlando last winter and  Jack Sellmeyer at the Radio Guide Seminar before the 
NAB in Charlotte.  Wow  see the Smith Chart of your common point as you tune 
it.

Dave Hultsman
Jackson, MS


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