Spehro Pefhany wrote:

> At 09:59 AM 2/13/02 -0500, you wrote:
>
>> But there definitely are audio frequency "RF" transmitters, and these
>> are
>> not "ill-designed products." For example, the U.S. Navy uses what
>> most would
>> consider as "Audio Frequencies" in their equipment designed to
>> communicate
>> with submerged submarines. Though efficiency is horrendous, the
>> importance
>> of the task makes the inefficiencies acceptable.
>
>
> The ELF transmitters in northern Russia, Michigan and Wisconsin are
> almost *beneath* the audio range (< 100Hz!).

NONSENSE!  They are <100KHz!

>
>
> Here's one take on it:-
>
> http://www.provcomm.net/pages/joe/introlf.htm
>
> "The "long wave" spectrums of frequencies are divided into three main
> grouping by convention. These are;
> LF (Low Frequencies) 535 to 150 kHz
> VLF (Very Low Frequencies) 150 kHz to 3 kHz
> ELF (Extremely Low Frequencies) 3 kHz to 300 cycles (approx.)"
>
> Best regards,
>
> Spehro Pefhany --"it's the network..."            "The Journey is the
> reward"
> speff@interlog.com             Info for manufacturers:
> http://www.trexon.com
> Embedded software/hardware/analog  Info for designers:
> http://www.speff.com
> 9/11 United we Stand
>
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>
>
>

--
  *
  |  __O    Thomas C. Sefranek  tcs@cmcorp.com
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