
WLW: 700 kHz, 500 kW, 100% modulation, no limiter (2000) - nkurz
http://www.ominous-valve.com/wlw.html
======
geerlingguy
I've worked in radio, got to work with the KMOX ('the mighty 'MOX' as many in
the Midwest, USA called it) transmitter, and even at a 'measly' 50 kW[1], it
was quite a power to behold.

The room where the power fed into the antenna regularly had charred remains of
field mice, squirrels, snakes, etc. that ventured too close to the high
powered connections.

It's a lot of power, and I can't imagine half a megawatt!

1\.
[http://www.stlmediahistory.com/index.php/Radio/RadioArticles...](http://www.stlmediahistory.com/index.php/Radio/RadioArticles/kmox-
the-voice-of-st.-louis-engineering-history)

------
keithpeter
UK: Radio 4 still puts out at least 400KW am on 198KHz for the time being, but
will be phased out in the next decade or so. There is something slightly magic
about pumping that much power into an impedance that is basically the air...

[https://en.wikipedia.org/wiki/Droitwich_Transmitting_Station](https://en.wikipedia.org/wiki/Droitwich_Transmitting_Station)

[http://www.bbceng.info/Operations/transmitter_ops/Reminiscen...](http://www.bbceng.info/Operations/transmitter_ops/Reminiscences/Droitwich/droitwich_calling.htm)

Edit: typically I can't find a definitive figure for the power output...

~~~
welterde
Deutschlandfunk also used to operate two 500kW (250kW at night) transmission
sites until the end of 2014. They were shutdown as a cost-saving measure (one
of the two sites was even upgraded to more modern transmitters just ~5 years
before the end).

[https://en.wikipedia.org/wiki/Sender_Donebach](https://en.wikipedia.org/wiki/Sender_Donebach)
[https://en.wikipedia.org/wiki/Aholming_transmitter](https://en.wikipedia.org/wiki/Aholming_transmitter)

------
wglb
The links at the bottom of the article are also excellent.

At the 2013 Dayton Hamvention, there was a tour of the facility shown here:
[https://www.youtube.com/watch?v=CbHjcwIoTiY](https://www.youtube.com/watch?v=CbHjcwIoTiY).
Apparently, the engineer who first designed the transmitter was barely 21.

------
josh-wrale
I drove under the WLW antenna for the first time recently. It's a
megastructure for where it sits.
[https://en.wikipedia.org/wiki/WLW#.22The_Nation.27s_Station....](https://en.wikipedia.org/wiki/WLW#.22The_Nation.27s_Station.22)

------
madengr
I picked up (what may have been) a 1 MW Algerian Longwave station yesterday on
150 KHz. My QTH is Kansas. LW propagation was very good yesterday.

~~~
knowaveragejoe
This?

[https://en.wikipedia.org/wiki/Kenadsa_longwave_transmitter](https://en.wikipedia.org/wiki/Kenadsa_longwave_transmitter)

~~~
madengr
Yes, probably. Female voice in English and French. It was at 150 kHz though,
not 153. Gone today. Propagation and noise were very good yesterday. I was
also seeing aviation NDB beacons on top of one another.

------
yock
The article briefly mentions VOA Bethany Station. That site was impressive to
say the least. The tops of the antennas would peek over the hills as you
traveled north on I75 from the Cincinnati suburbs, coming into full view as
you passed Tylersville Rd. It was sad to see such a historic site disappear,
and of course now it's a complex of chain stores and restaurants like every
other recently developed chunk of land in the Midwest.

------
samfisher83
Why did the FCC allow for a 500kW transmitter? What did powell have to do to
get it?

~~~
hga
Reading the Wikipedia article, it sure sounds like it was worth trying out
once as an experiment. At the very least, it established that 50kW was a good
maximum.

~~~
skrause
Globally 500 kW transmitters aren't actually that special, Europe has a lot of
transmitters even more powerful, some transmitting at up to 2000 kW:
[https://en.wikipedia.org/wiki/List_of_European_medium_wave_t...](https://en.wikipedia.org/wiki/List_of_European_medium_wave_transmitters)

I'm honestly wondering why 50 kW is considered a good maximum in one part of
the world while others have way more powerful stations...

~~~
jccalhoun
My guess would be public vs private. A lot, if not all, of the stations on
that list seem to be government owned but in the USA they are corporate owned.
2000kW is fine if you own all the airwaves and don't have a company in the
next city over complaining that you are crowding out their airwaves (of course
they might have had other countries complaining...)

~~~
hga
I suspect you're right, and WLW did have to modify its antenna setup due to
issues with Canada.

------
madengr
Sad to see these stations going off the air. Yes, you can stream all this now
over IP, but there is still something fascinating about tuning across the
spectrum at night time and receiving transmissions from distant lands.

------
alokedesai
For those who are curious, this is what the current WLW radio tower looks like
in Mason, OH ([http://www.johninarizona.com/wlw/wlw-700-cincinnati-oh-
tower...](http://www.johninarizona.com/wlw/wlw-700-cincinnati-oh-
tower-2013-johninarizona.jpg)). It's hard to get a sense of how big it is in
the picture but this thing is MASSIVE

------
ddingus
That is a fun read. I love AM radio for this kind of history attached, and
because I was a HAM as a kid. Spent many fun late nights in front of various
glowing tubes, listening and transmitting on a variety of antennas, all made
from what one could find around the rural setting I lived in.

Love this: "for when it blew up, which everyone knew it would..."

------
viraptor
This article is great. But I realised it gets so much better if you read it in
the voice of 60s tech advertisement.

------
theoh
Similar to Hugh Stegman (operator of Ominous Valve) is Tom Jennings:
[http://sensitiveresearch.com/](http://sensitiveresearch.com/)

------
titusnicolae
tesla model S has over 500kW peak power

~~~
m4x
Sure, but the Model S isn't radiating most of that power into the air around
you :)

It's pretty amazing to think that there are electromagnetic fields with
hundreds of kilowatts of power shooting out around those antennas.

You wouldn't want to stand too close

