Scott wrote that KKOL's patterns send a narrow beam to the north. That can be said of the night pattern, which uses all four towers--although the beam is centered to the northwest, not the north. The "half-power" points (relative to the equivalent power at the radiation maximum) are 88 degrees apart. At zero degrees (due north), the signal, though still quite strong, has already dipped below half of the equivalent power at the (313-degree) radiation maximum. The signal strength falls pretty rapidly as you move clockwise from due north; IIRC, the NIF contour does not cover a small area on the east side of Seattle. The day pattern (three towers) is not narrow, however. It resembles many two-tower figure eights. Although the radiation maximum is pretty much due north, the signal strength over an arc of almost 100 degrees from the northwest to the east-northeast is greater than the equivalent of 100 kW (based on the pattern RMS). The third tower is used mainly to introduce a slight bit of asymmetry into the pattern; the two minima are at 159 degrees (south-southeast) and 260 degrees (west-southwest). Of these, the minimum at 159 degrees is the deeper of the two; it brings the signal down to an equivalent power of 315W. In the minimum at 260 degrees, the equivalent power is a skosh more than four times as great: 1268W.
-- Dan Strassberg, [EMAIL PROTECTED] eFax 707-215-6367 _______________________________________________ IRCA mailing list [email protected] http://arizona.hard-core-dx.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]
