Does anyone know what frequencies aircraft us when going over seas?  I have
heard it is hF but I'm not to sure.
Blake

-----Original Message-----
From: Blind-Hams For blind ham radio operators
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Sent: Thursday, November 13, 2003 6:42 PM
To: [log in to unmask]
Subject: Re: OT - Line Voltages, Frequency in History


Message-Id:
<20031113184200.WMDK17368.imf20aec.mail.bellsouth.net@[68.212.98.27]>

Martin wrote:
   >As for why aircraft use 400 HZ, you are all right but there is
   >even one more reason.  While I don't know why the exact number of
   >400 Hertz, the biggest reason for using a higher frequency is the
   >size of inductors such as what you have in motors and transformers.
<snip>
   >I think that we'd get pretty tired of hearing that mosquito
   >whine everywhere very quickly.
I get my share of aeronautical mobiles check in with me when I'm ncs
for the Maritime mobile service net and you always hear a hint of that
400 hz and its harmonics.

Also note that on hf a lot of the aero comms sound like there's a
little rf feedback into the audio.  Harder to get a good ground up
there <grin>.

73 de nf5b



Richard Webb

Electric Spider Productions
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