Re: [IRCA] KABN (Re: Halp!)

[Scott Fybush <scott@xxxxxxxxxx>]

At 12:11 PM 12/8/2005 -0800, you wrote:
>Scott,
>
>With 500w, couldn't Concord set up a directional pattern with the lobe
>directed due West without signal to the N, E, or S? Didn't they have 4
>or 5 towers? But would it be cost effective? Probably better to change
>frequency or move the operation elsewhere.

That's pretty much what they had, until the value of the land under the 
towers got to be considerably more than the value of the station itself.

To rebuild now would present two problems. First of all, they'd have to 
protect everything they were protecting before. In particular, there's KYOS 
on the same channel, 91 miles away. KABN's 0.025 mV/m contour can't touch 
KYOS' 0.5 mV/m contour, and vice versa. This is one of those rare cases 
when radio-locator.com is actually useful for something - the middle (blue) 
contour is the 0.5 mV/m, more or less. KYOS'  covers Stockton and extends 
almost into Contra Costa County, where Concord is located. Its 0.025 mV/m 
contour looks like it actually overlaps the old KWUN/KABN transmitter site, 
which would now be considered prohibited overlap. (Radio-locator's 
outermost contour is the 0.15 mV/m contour, which has no meaning in the 
allocations rules; the 0.025 mV/m contour is considerably larger.) KABN may 
be able to get that overlap grandfathered, but even so - any signal from 
KABN has to have a very deep directional notch towards Merced. That means 
lots of towers, and lots of towers mean lots of land, which is incredibly 
expensive in the Bay Area.

So why not move elsewhere? You've got a serious first-adjacent problem to 
the northwest, with KTOB 1490 in Petaluma. For a first-adjacent, your 0.5 
mV/m can't touch the other station's 0.25 mV/m, and vice versa. When you're 
surrounded by the salty water of the Pacific Ocean and of the San Francisco 
Bay estuary system, those contours spread out like crazy. KTOB's 0.5 almost 
reaches the old KABN/KWUN transmitter site, and the same is true in 
reverse. Again, this was probably grandfathered under an older set of 
rules, but that grandfathering would be unlikely to apply to a change of 
transmitter site. You can't go south, because you can't overlap 5 mV/m 
contours with KSJX 1500 in San Jose, and you can't do much with moving east 
towards Oakland, because you can't overlap 25 mV/m contours with KPIG 1510 
in Piedmont. (Overlaps are permitted over uninhabited areas of water, but 
not over land, and there would be considerable overlap over land.) You 
can't go northeast, because there's also what looks like prohibited overlap 
to KIID 1470 in Sacramento. And whatever you do, you have to put 25 mV/m 
over at least 80% of your city of license, Concord, unless you apply for a 
COL change during a major change window - and then that would leave Concord 
with no "local" service, which the FCC wouldn't find acceptable.

This, incidentally, is all just for the daytime side of things. At night, 
you've got even more issues, what with the FCC's "ratchet rule" and other 
arcana that makes moving a full-time AM signal a real challenge nowadays.

(Grandfathered overlaps like these, which are not uncommon in 
densely-populated, high-conductivity areas like the San Francisco Bay, are 
going to be one of the biggest issues with IBOC on AM, if any of the 
affected stations ever try to use it. Nobody really knows just how bad the 
mess would be between, say, KYOS-KTOB-KSJX-KPIG if and when any of them go 
digital, even by day.)

And a frequency change would be nearly impossible - there aren't any spots 
on the "standard" dial that would offer much improvement on this ugly 
picture. This was, if memory serves, one of the tightest squeezes ever made 
to get a station on the air in the first place, one of those stations that 
was so directional that you could see the towers before you could hear the 
signal, if you approached from the back end of the pattern. It would 
probably have been a great candidate for an X-band move, but I don't 
believe it ever applied during the initial window, which is too bad.

The only real option, if someone truly wanted to pursue this, might be to 
make engineering changes at KYOS and KTOB instead. If KYOS moved from DA-N 
to DA-1 with its night pattern, it would allow some more wiggle room for 
Concord. I have a hunch that's what Chester (who's a good guy) may have had 
in mind when he bought KWUN, but it clearly didn't work out that way.

s

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