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<BR> Douh! ;-) Damn you metric system <BR>
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Regards<BR>
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Pete<BR>
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> Date: Thu, 7 Jul 2011 12:56:17 +1000<BR>> From: kevind@esi.com.au<BR>> To: ozaprs@aprs.net.au<BR>> Subject: Re: [OZAPRS] Homebrew HF APRS transmitter<BR>> <BR>> G'day.<BR>> <BR>> On 07/07/11 12:39, Peter Wicklein wrote:<BR>> <BR>> > Since you are obviuosly a risk taker and like to stir the pot a bit ;-)<BR>> > and have brought the subject of netting back up again... I thought I<BR>> > thought I would joint you and say I'm surprised that nobody has<BR>> > discussed the issue of the effects of doppler on mobile stations and how<BR>> > it affects the the signal at 10MHZ. and what it will do to all the hours<BR>> > of alignment that people are currently perfoming. See my calcs below.<BR>> <BR>> A small misteak in your calcs - you've specified the speed as 110 km/s, <BR>> not km/h. About 3600 times the effect :-)<BR>> <BR>> Doppler shift at 10MHz at 110 km/h is roughly 1 Hz.<BR>> <BR>> Kevin<BR>> _______________________________________________<BR>> OZAPRS mailing list<BR>> OZAPRS@aprs.net.au<BR>> http://lists.aprs.net.au/mailman/listinfo/ozaprs<BR></DIV> </div></body>
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