In a message dated 3/19/2005 12:36:34 P.M. Central Standard Time,
k6rix@earthlink.net writes:
I need an education here...
When the FCC gives the "Electrical Height" (in degrees) of a broadcast
tower as 175.7 degrees, what does that mean?
In this situation, I'm specifically talking about the (former) KFI tower in
Los Angeles. It has been my understanding that this 750' tower is about a
5/8 wave length at 640khz. The "degrees" leads me to believe that it is
just under a 1/2 wave (180 degrees).
I believe the size/mass of the tower can change the actual wavelength of
the tower just as electrical length of stepped elements are different
depending on their configuration. In other words, a 750' tower with a 10'
face is resonate at a different frequency than a 750' tower with a 6' face.
Can someone help me out here?
Dino...k6rix@earthlink.net
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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One wavelength in feet= 984/f(MHz)=1537.5 ft for 640 KHz. 750 ft tower =
750/1537.5 wavelengths=.4878. Electrical length=.4878 times 360=175.61. Pretty
close to the FCC figure.
73/k5gw
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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