[Lf] [Fwd: LF: Re: Calculating ERP from measured field strength]

[Andre Kesteloot]

Reg Edwards wrote:

> Hello Dick and all,
>
> Thanks very much for your figures.  I am not srprised at program predicting
> accuracy because attenuation is not very much different from 6dB for every
> doubling of distance and not much affected by type of ground.  I consider
> +/- 3dB to be not very much where 300 km radio propagation is concerned.
> ;o)
>
> I have just checked the source code in program GrndWav3.  It does make use
> of CCIR curves and data for refraction over the horizon although I have had
> to use some intelligent guesswork to extend to 30 MHz.  It's good to be
> reassured I havn't introduced any bugs.
>
> What DOES surprise me is the accuracy of the group's measurements.  There
> should be prizes given for such careful meticulous work !
>
> When available I would be pleased to have some figures of 500 to 2000 km
> propagation.
>
> ========================
> Regards from Reg G4FGQ
> Free Radio Design Software
> Go to  http://www.g4fgq.com
> ========================
>
> ----------------------------------------------------------------------------
> -------
>
> > Reg Edwards, G4FGQ, has a free  program called "Grndwav3" on his web site:
> > www.btinternet.com/~g4fgq.regp/page3.html#S301.
> >
> > Entering Jim's EMRP=218mW and distance 329km the program predicts for the
> > field strength at PA0SE the following:
> >
> > Sea water: 10.35 microvolt/m
> > average:       8.18 microvolt/m
> > pastoral:       9.50 microvolt/m.
> >
> > I measured 11 microvolt/m so Reg's program can also be used when the CCIR
> > curves are not available.
> > 73, Dick, PA0SE