[BC] 750-kW Class IA AMs

[Kevin Tekel]

Dan Strassberg wrote:
> Are there any superpower MW stations, in, say, the Middle East or
> Russia that run as much as 3 million watts? If so, how do they do in,
> say, southern Spain or Portugal during daylight hours?

I have no idea if this is still in use today by what is now the Voice of
Russia, but the 1995 World Radio/TV Handbook describes the high-power,
highly directional "Zarya" antenna array, used by what was then Radio
Moscow's Popovka transmitter site, 30 km southeast of St. Petersburg:

"For Radio Moscow's external services to Scandinavia in the evening, the
1494 kHz transmitter is switched to a highly-directional antenna system
called 'Zarya', which produces a gain of 25 dB at an azimuth of 256
degrees.  This Beverage-type system has 26 equidistant masts on a
straight line and a total length of about 2500 meters (1.55 miles)!"

A photo caption mentions that the masts are (were?) spaced about 100 m
(328 ft) apart and the height of each mast is just over 40 m (131 ft).
The text also mentions that the Zarya array is fed by a 2000 kW
transmitter which was then currently running at 1200 kW.  With 25 dB of
gain, that's a _serious_ amount of ERP!

The Popovka site is/was one of about a dozen sites which had/have a
Zarya antenna system, which were designed in three different sizes of
mast height and spacing.

Anyway, back here in the USA, I don't think there should be any
restriction on the power level of Class A stations.  If you can fit a
750,000-watt signal into the current allocation scheme, meeting all
application protection ratios both nationally and internationally,
then by all means, go for it!  However, in many cases, the "NIMBY"
factor alone would be enough to effectively prevent stations from 
upgrading far beyond their current 50 kW.  Maybe 100 or 150 kW would
be feasible (as it is in Mexico and many other countries), but once you
start planning 500 kW or more, I doubt local residents would be happy
when their flourescent lights stay on all the time and they start
hearing Rush Limbaugh talking to them from their toaster oven.



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