Hi all,

Interesting (at least to me!) while FM DX'ing last night...

I live in Michigan (USA) in a very southern area of the state.

So I was surprised last night when I heard an FM Radio station is in a town a little over a hundred miles from me.

Turns out that FM WBCT has the unique distinction of having THE HIGHEST power output of an North American radio station!!! 

From Wikipedia:
"WBCT is a Class B "Superpower Grandfathered" station, meaning its power was granted before the Federal Communications Commission set maximum standards for FM radio stations."

It turns out that this town, Grand Rapids, has two other "Superpower Grandfathered" stations in it as well!  One at 265,000 watts and one at 96,000 watts.  Crazy!

No wonder I could hear it!  ;)


Johnny

One at 265,000 watts and one at 96,000 watts.  Crazy!

What's so exceptional about that? At my location there are five 100 kW transmitters on the same mast, and across the border in Germany there are five 80 kW on one mast.

Martin.

There are other grandfathered superpower FM's in other states...I don't have the details right now but I know there is one in Virginia.

Jay

Hi Martin,

I guess it's just my first exposure to a station with this much power!  :)

Your location sounds pretty "powerful" too!


Johnny

Hi Jay,

I wasn't aware...  very interesting!


J

On Wed, Mar 9, 2022 at 9:39 AM Johnny via groups.io
<jlochey@...> wrote:

Hi Martin,

I guess it's just my first exposure to a station with this much power! :)

The FCC has capped AM station power at 50 kW for decades and decades.
WLW had an STA (or whatever they called it before WW2) for 500 kW and,
IIRC, there were a few others that experimented with Super Power but
those were gone by the 1950s.

If there is an actual FCC cap for FM, I don't know what it is. Pretty
sure there are plenty of 100 kW FMers. But 100 kW on VHF and 100 kW
on MF are two different things.

Also note that I specifically mentioned FCC because *none* of this
applies to other countries. There are *megawatt* stations on the
"standard broadcast" bands in other parts of the world. There used to
be the same on the LW band as well, but I am not certain if those
exist any more - LW stations are going dark quickly.


Off to dig up the maximum for FM in the US ...



--
Peter Laws | N5UWY | plaws plaws net | Travel by Train!

On Wed, Mar 9, 2022 at 9:49 AM Peter Laws via groups.io
<plaws0@...> wrote:

Off to dig up the maximum for FM in the US ...

100 kW apparently (*files that for future reference*). That's the
best you can do and most stations are 10 or more dB down from that.
Like AM, just because that's the max legal power doesn't mean any old
station can run that if they have the money.



--
Peter Laws | N5UWY | plaws plaws net | Travel by Train!

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