Michael Graham to be on WCRN, 3 other stations
Tue Feb 5 23:37:28 EST 2013
On 2/5/2013 1:54 PM, Dan.Strassberg wrote:
> On a good radio, a 2.5 mV/m daytime signal is usually listenable, as
> long as interference from all of the stuff (fluorescent lights and light dimmers,
> for example) that raises the AM noise floor is not too severe. But 2.5 mV/m
> is hardly what most people--even radio geeks--would call a strong signal.
> The FCC considers 5 mV/m (twice the field intensity at R-L's inner contour)
> to be the minimum for service to a station's CoL.
Experts whose opinions I trust tell me that in major markets where it's
possible to do some fairly granular breakdowns of ratings data, the
evidence is now clear that mass-market AM stations get essentially no
listeners in areas where their signals are less than 10 mV/m - and
that's rapidly edging up to 15 mV/m as "all that stuff" continues to
raise the AM noise floor. (Stations with specialty formats still draw
audiences at lower signal levels; if the music you want can be found
only on WJIB, you'll make a much bigger effort to tune in 740 even if
you're in an area where its signal is weaker.)
If R-L showed the 15 or 10 mV/m contours, they'd be significantly
smaller than the 2.5 mV/m "inner" contour now shown.
More information about the Boston-Radio-Interest