"K7ITM" wrote in message
...
On Aug 5, 7:31 pm, "Walter Maxwell" wrote:
Do really believe that there was a transmitter in the 1920's that could
deliver
500 kw?. The first station that could come up with that amount of power
was in
the 1930's,W8XO, the experimental station of Powell Crosley, that became
WLW
again when the experimental period was over. Are you aware of the
technical
difficulties that obtained in just getting that monster to work? General
Electric and Westinghouse supplied most of the parts, the rest by RCA,
and RCA
was the company that strived and strived before it was workable at that
power
level. I once worked for Harold Vance, the RCA engineer in charge of the
project. Certainly this didn't happen in the 1920's, and not in
Schenectady.
Somebody's been
feeding you horse hockey.

Walt, W2DU

On the other hand, there were spark transmitters well before that in a
similar power class. As I understand it, the powers actually achieved
as output were often either not well known or were kept quiet for
various reasons, but they were clearly in excess of 100kW. Apparently
the Oct. 1920 issue of "General Electric Review has an article by
Alexanderson about a 200kW alternator-driven transmitter. I
understand that there were also some high-powered (Poulsen) arc
transmitters (quite distinct from the shock-excitation of spark). I
found one reference to a Poulsen arc transmitter that ran at 3.6 MW
input power which was "still active in the early 1920s..." It ran on
~50kHz. Pretty much all this early stuff was below 100kHz, which of
course yields very reliable propagation if you put enough power into
it.

But WLW ran 500KW of 100% AM modulation. I understand just the modulation
transformer was the size of a room in order to handle the 250 KW of audio. I
believe it was on 700 KHz. See the link I gave above.

Tam/WB2TT

Our plant used to be less than a wavelength from a 1MW transmitting
system, and I was always somewhat surprised that we weren't bothered
more by them, as we made sensitive spectral analyzers that covered the
frequency range on which they transmitted. We moved, and now we're a
couple wavelengths away. We're more bothered by the 5kW AM broadcast
station a few miles away, though that's easily filtered/shielded.

Cheers,
Tom