Patrick Martin wrote: > Scott, > > One question. Now if they do have a taller tower, dropping to 690 watts > from 1 KW, would I get exactly the same signal (S meter reading) than I > got before. In otherwords, would the 690 watts get out as good as the 1 > KW?
That's more or less the idea. Within the limitations imposed by a given station's class (no more than 1 kW for a class C "graveyarder," no more than 50 kW for class A, B and D stations), the FCC's not concerned as much with how much power goes INTO the antenna as with how much field strength comes out of it. In the case of a station like KSLM, it's pretty well locked into its existing contours by everything else on and near 1390, so changing transmitter sites or towers won't buy it any more reach. What the FCC looks at in a move like that is where the signal contours fall, which is a function of both raw power into the antenna and the antenna efficiency. The 690-watt level was no doubt chosen to produce the same field strengths that 1000 watts did from the old tower, which means the signal you receive should be about the same. Back in the days before "dial-a-power," when the FCC only allowed stations to operate at certain fixed power levels (1, 5, 10 kW, etc.), it was not uncommon for stations to deliberately reduce the efficiency of their antenna systems to be able to use the next power level up. So a station that might not quite fit in at 5 kW, but which wanted more reach than 1 kw would give, might apply for 5 kW with an antenna system that included a big resistor to dissipate some of the power along the way. Today, that station would simply be licensed at 3200 watts, or whatever. s _______________________________________________ IRCA mailing list [email protected] http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: [email protected]
