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At 02:50 PM 3/22/98 +0000, you wrote:
>As I understood it, the largest ERP of any FM is in Michigan.  WBCT,
>93.7 Grand Rapids (originally WJFM, licensed to Kalamazoo) runs 320kw at
>ft, for an effective 500kw.  During its WJFM days, the Fetzer family ran
>in Broadcasting bragging about its big signal...full page, at that!  In
>same market, WOOD-FM 105.7 runs 265kw at 810 ft.
>As for other C's in the Northeast, how about the former WRUN-FM Utica,
>WMJQ-FM Buffalo, WBUF Buffalo, WYYY Syracuse....all are grandfathered
>with anywhere from 93 to 140kw. on big sticks.  WNCI Columbus runs
>something on the order of 175kw.
I kind of hate having this discussion over and over. I've had it several
times at Airwaves. You are right about other stations having ERPs higher
than WHOM's, As for the Michigan station, its ERP is equivalent to 500 kW at
_some_ antenna height, but it is NOT even equivalent to 100 kW at 2000'.
(It's equivalent to something more like 50 kW at 2000'.) ERP alone does not
predict FM coverage. The predictor is a combination of ERP _AND_ HAAT. To a
first order, ERP must be reduced by the square of the ratio of the actual
HAAT to the maximum HAAT that is permitted for stations of the same class
that operate with full power. I contend, though several in the group
disagree (wrongheadedly, I insist), that the best way to compare FM "ERP"s
is to normalize them to the maximum permitted antenna height for the station
class. If you do that, only three stations in the US head the list, and of
those, because of its distance from the coast, WHOM wins on coverage area.

BTW, although several group members maintain that normalizing as I described
above does not produce valid comparisons among the coverage areas of
different stations, it is exactly the technique that the FCC used to use to
determine the ERP that it would permit for an FM whose antenna height
exceeded the class maximum and whose coverage was not limited by
interference to other stations.

- -------------------------------
Dan Strassberg (Note: Address is CASE SENSITIVE!)
ALL _LOWER_ CASE!!!--> dan.strassberg@worldnet.att.net
(617) 558-4205; Fax (617) 928-4205