jry said:
I asked my engineer what power level would it drop to (day and night) if you just wanted it to go non directional. The answer wasn't very good.
Your engineer is quite right. A non-directional antenna, in most cases, would mean a signal that does not surpass the minimum signal strength of the station's directional array. In the case of WDCD that is about 75 mV/m at 1 kilometer on the 185 degree radial. Doing the math - IDF/RMS squared times the power out - that works out to 37 watts that they could license non-directionally! That is based on the station's RMS efficiency, which is about 2743 mV/m, divided by that minimum field strength of 75 mV/m, squared, times 50,000 watts.
Of course all of that is theoretical, and would probably be more accuate for the night power given protection requirements for ZNS-1 and KXEL. With changes on the AM dial since the pattern was licensed in 1947, they may be able to get more non-directional power than that during the day. For instance, there is no longer WBAZ, 1550, in Kingston to protect. The closest daytime co-channels to protect are WSIV in East Syracuse and WNWR in Philadelphia. CHIN in Toronto would probably not be a daytime issue because WSIV is between it and WDCD. First adjacents to protect would include WUSP in Utica and WSDK in Bloomfield, CT on 1550, and WDJZ in Bridgeport on 1530. Second adjacents to protect would be WIZZ in Greenfield, MA and WWKB in Buffalo on 1520, and WQEW in New York on 1560. The only third adjacent to be considered would be WVTL in Amersterdam on 1570. All in all, they could very well get between 10KW and 25KW daytime non-directional.
However, if I were going to buy the station, I would do a serious daytime allocation study to see just how much the 50KW pattern could be let out to make it more viably cover the metro, and then keep the current night pattern.
Ah, speculation is fun.....