Re: [IRCA] Promoting our hobby

[Scott Fybush <scott@xxxxxxxxxx>]

The whole "clear/regional/local" distinction referenced in James' 
article more or less went away the last time the AM allocations system 
was revised.

The old "class IV" local stations ("graveyarders") remained 
substantially unchanged, though they're now known as "class C." They're 
still the only operations you can have on the six graveyard channels, 
and are still limited to 1 kW, usually ND.

But the rest of the dial changed, quite dramatically. The old class III 
stations that we thought of as "regionals" - no more than 5 kW, usually 
DA-N - were merged into an international "class B" that also includes 
some of the stations that used to operate as class II facilities on the 
"clear channels."

There is *no* regulatory distinction anymore between those two groups of 
"class B" stations - if you can squeeze a 50 kW signal on the dial, you 
can do it at 1320 just as easily as you can do it at 780 nowadays.

Because the dial was already pretty densely packed before the rules 
changed, most of the class B stations that were able to increase power 
from 5 to 50 kW on the former "regional" channels are on or near the 
coasts, aiming most of that extra power out to sea or out of the country.

The first such station was WTMJ 620, about 15 years ago.

The stations we once knew as "clear channels" are today's class A 
stations, and what distinguishes them from the 50 kW class B signals is 
this: the class A stations enjoy interference protection for their 
nighttime skywave service, while the class B stations are protected only 
for their groundwave coverage.

There is no longer any regulatory distinction between the old "I-A" and 
"I-B" clears. The I-As used to be protected from essentially *any* 
interference to their nighttime skywave, allowing them to run 50 kW 
ND-U. The I-Bs generally had to protect at least one other co-channel 
station at night (think WBT/KFAB or WKBW/KOMA).

s
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