WNSH PSRA/PSSA

[Dan.Strassberg]

The following has to provide an illustration of just how messed up the
FCC's Media Bureau engineering must be. I looked up WNSH's PSRA and
PSSA, which you can find by doing a station search on the call letters
in CDBS and then opening the link to "Correspondence." As we know,
WNSH is licensed to operate all night with 85W ND. Yet the PSSA and
PSRA were recalculated earlier this year to limit the power from
6:00AM local time to sunrise and during the two hours immediately
following local sunset to just 4W. The limiting station is not the
nearby Class B CFAV but, rather is Mexican Class A XERF.

Now, as I understand it, a full-time authorization the permits higher
powers than a PSRA/PSSA trumps the PSRA and PSSA so WNSH's PSRA and
PSSA seem to be purely academic. But the idea that the Cookie Company
could have made such a wildly erroneous calculation is not. My guess
is that the low powers are based on facilities that XERF has not used
for almost half a century (250 kW ND) AND on rules about protections
required of US stations to foreign co-channel Class As that have not
been in effect for almost a quarter century!

The only way I can imagine WNSH being limited to 4W to protect XERF is
if the contour being protected is XERF's 250-kW 0.5 mV/m 50% skywave
WITHIN US borders. In all likelihood, that contour lay very close to
Boston. I remember hearing XERF at night in Cambridge in 1959. The
Mexican border blaster was running 250 kW back then and the guy on the
air sounded an awful lot like Wolfman Jack, although he used the
on-air name of Dr Jazz-Mo. However, as I understand it, since the Rio
treaty of the early 1980s, US AMs on Mexican Class A channels have
been required to protect the skywave service of Mexican Class As only
within Mexico. Since XERF is only a short distance from the Rio
Grande, its signal along that border probably doesn't drop to anything
like 0.5 mV/m until you are well byond Texas--most likely in New
Mexico or even Arizona. So the distance from Beverly is probably more
than 2000 miles. I think that, at that distance, it is most unlikely
that 85W ND or even considerably more could do much damage to XERF--if
it were running 250 kW, which it no longer does. (I believe it
actually runs 10 kW and has long-unbuilt CP for 50 kW.)

-----
Dan Strassberg (dan.strassberg@att.net)
eFax 1-707-215-6367