Re: LF: 500khz rtty

[Rik Strobbe <Rik.Strobbe@fys.kuleuven.be>]

Based on the antenna description given by Mal ("1/4 wave inv L for 500  
khz, 100 ft vertical and rest horizontal") simulation reveals a  
radiation resistance of 5 Ohm and a directivity of 1.5 dBd. This means  
that only 375 mA antenna current is needed to radiate 1 W ERP.
It is hard to tell from here, but such a big antenna should have a  
loss resistance of 20 Ohm or less. So in the worst case 2.8 Watt TX  
power is needed to get 1 Watt ERP.
I can only dream of such a situation ;-)

73, Rik  ON7YD - OR7T

> From: "mal hamilton" <g3kevmal@talktalk.net>
> Sent: Saturday, August 23, 2008 8:18 PM
> To: <rsgb_lf_group@blacksheep.org>
> Subject: Re: LF: 500khz rtty
>
> > ANYTIME . If you saw the fet in my PA you would'nt bother.
> > G3KEV
> >
> > ----- Original Message ----- From: "John Pumford-Green GM4SLV"   
> > <gm4slv@sighthound.demon.co.uk>
> > To: <rsgb_lf_group@blacksheep.org>
> > Sent: Saturday, August 23, 2008 7:39 PM
> > Subject: Re: LF: 500khz rtty
> >
> >
> > > On Sat, 23 Aug 2008 18:14:23 +0100
> > > "mal hamilton" <g3kevmal@talktalk.net> wrote:
> > >
> > > > I thought that would be the response from you. Why no ID?
> > > > I will let OFCOM decide if necessary
> > > > G3KEV
> > > Perhaps we could ask them to check your ERP at the same time?
> > >
> > >
> > >
> > > No virus found in this incoming message.
> > > Checked by AVG - http://www.avg.com
> > > Version: 8.0.138 / Virus Database: 270.6.6/1626 - Release Date:   
> > > 8/21/2008 6:54 PM
> >
> >
> >
> > No virus found in this incoming message.
> > Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus   
> > Database: 270.6.7/1628 - Release Date: 8/22/2008 18:32


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