PSSA parameters vs Nightime

[mbrg]

I found the 2007 FCC PSSA/PSRA parameters on the FCC's website, in the correspondence folder, for 2 am daytime stations in my realm.

Also I see a Daytime and Nighttime license.

The Daytime (1Kw) power is as it's always been and the Nighttime power is the lowest wattage from the original PSSA sheet in the 80's (23w).

The newer PSSA values are completely different from the originals from the 80's, and for both stations, the latest (lowest) power lower than the listed nighttime ( 5w).

Which one is right?

Is this due to the adjustment of Daylight Savings Time into March and October?

Thanks!

 

[TomT]

Don't think those website values are in effect. I would follow the values on the station license--if listed.

 

[Schroedingers Cat]

Who knows why the values are different.

If you were still using the original approved power, I think the radiation toward protected stations cochannel and adjacent channel don't have to be reduced to 25% RSS values, just maintained. That's according to some applications I have seen, anyway. If you were in the 50% RSS computation of a station with your PSSA, it was probably a mistake on the FCC's part.

Most applications just put it under the 25% RSS for domestic stations, just like a new Class B facility would have to do.

The RSS contributors seem to be pretty accurate empirically for DXers, unless a station is using a power or pattern at night that they shouldn't be. You can't tell an experienced DXer that a station operating with 100 watts or less is going to be heard for more than brief periods, and not on a daily basis, unless it's practically in the middle of nowhere.

 

[DanStrassberg]

I found the 2007 FCC PSSA/PSRA parameters on the FCC's website, in the correspondence folder, for 2 am daytime stations in my realm.

The newer PSSA values are completely different from the originals from the 80's, and for both stations, the latest (lowest) power lower than the listed nighttime ( 5w).

Which one is right?

Is this due to the adjustment of Daylight Savings Time into March and October?

Here's my recollection of the story; take it for what it may or may not be worth: It was indeed due to the change in the start and end dates of DST and the new values were wildly at variance with the old. for which the FCC had, umm, lost its records. A few stations were granted substantial PSSA power boosts, but most saw their PSSA power dramatically reduced (some from 500W to as little as 1 or 2 watts).

These new figures had been published for less than a week and were due to go into effect in only another couple of weeks, when the Cookie Company, in a classical Emily Litella moment, told the daytimers to "never mind." Although corrected values were promised before the end of the 2007 DST season, they were never announced; the the FCC is apparently hoping that nobody remembers those erroneous 2007 values.

Oh, and the word was, if you've got that old paper PSRA and PSSA from years back, rent a safety deposit box and keep them there. Post photocopies at the station. Those old yellowed pieces of paper are all you've got and they're the world's only surviving records of what your station was granted.

Also, and I may be wrong about this, I think you are now allowed to continue using the October power-increase/cut-back times from the original authorizations for the few days until DST ends in early November.

 

[Schroedingers Cat]

I would assume that if you are authorized just 5 watts, you are more than likely close to the protected contour or national border for a Class A station (or one considered to be Class A under international agreements).

I have seen a few with just 5 watts on regional channels, but these usually are directional with the maximum directly toward a very well protected Class B with an NIF of 3 mV/m or less. I'd say almost all nondirectional PSSA authorizations on Regional channels are at least 15 watts.

 

[NHRadio]

WJIB 740 Cambridge MA has 5 watts at night, I believe.

 

[DanStrassberg]

WJIB 740 Cambridge MA has 5 watts at night, I believe.

WJIB is WELL inside of what would be CFZM's protected nighttime contour (0.5 mV/m 50% skywave) if CFZM were a US station, which it is not. Like all North American stations, CFZM receives protection only over land areas of its country of license. So WJIB has to protect the point where CFZM's 0.5 mV/m 50% skywave contour intersects the US-Canada border. That point probably lies somehere over Aroostook (spelling?) County in far northern Maine. That is how WJIB's 5W night power was calculated. If Toronto were part of the US or Cambridge MA were part of Canada, WJIB could not operate at all at night.