Some of you know that KYPA-1230 Los Angeles probably has the weirdest and least efficient antenna currently in use. See one of Scott Fybush's three excellent pages regarding AM antennas in LA; http://www.fybush.com/site-020327.html. KYPA is still using a "hammock type" horizontally polarized antenna reminiscent of the 1920's and 1930's. It may be the only one still in use. Not only that; it's electrical length (normally referred to as electrical height!) is an anemic 27 degrees (the commonly used quarter wavelength antenna has an electrical height of 90 degrees).
KYPA has a CP to move to a tower that is still standing but hasn't been used in decades. It's at 541 South Spring Street in downtown Los Angeles, and still sports the long forgotten KRKD (1150) call letters. They would run 540 watts day and night from there. The tower probably hasn't been used in 50 years. Probably quite by coincidence that tower works out to an even quarter wavelength at 1230, at least according to the FCC web site, where all of this hopefully accurate data came from. But apparently there are problems with how to properly ground the antenna and possible excessive RF exposure to nearby people and buildings.
So now KYPA has applied to diplex off one of 50 KW KBLA (on 1580)'s 6 towers. They would run 900 watts during the day and an even l KW at night. Maybe somebody can explain that inconsistency to me. See more of Scott's great photos and fascinating information at http://www.fybush.com/site-020313.html; including the lowdown on KBLA's towers. KYPA is really lucky. For some reason those towers were built at a odd electrical height for 1580; 115.6 degrees. However at 1230 the electrical height is, get this, 89.52 degrees, about as close as you can get to an ideal 90 degrees. It should be quite interesting to see how this all works out.
The URL for the third part of his visit (and photos) of LA's AM antenna sites is http://www.fybush.com/site-020320.html. All 3 are well worth looking at.
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