Sorry about the mistake in the classification. However I easily receive ZNS3,
Freeport, Bahamas, on 810 khz day and night from Florida. The announcer says
that the station's power is 10 kw.


ZNS3 isn't in the FCC database, but what else is new.

Even if it was 50 kW, it would be a Class B as the Bahamas has no Class A
priority on 810.

ZNS1 operates 50 kW DA-1 mainly because after "Rio" any Class I-A had to
operate with 50 kW (U.S. and Canada, et. al.) and "at least 50 kW" (Mexico) in
order to retain Class I-A status.

Before, ZNS1 (a Class I-A) operated with 10 kW, and Canada's 1580 Class I-A
also operated with 10 kW.

Class I-Bs and Class I-Ns can be grandfathered at 10 kW , but Class I-As can't
be.

This, not withstanding XERF operating with 10 kW for decades now.

The U.S. isn't going to force the issue with Mexico and demand that XERF
operate with its "notified" 250 kW, simply becuase there is not that much
utility power available in the area, and, anyway, the 250 kW transmitter
doesn't exist anymore.

But, the Bahamas' 1540 and Canada's 1580 were indeed forced to move to 50 kW,
which required both to install directional antennas to protect stations of
lower class in the U.S.