On 2/21/2012 8:26 AM, Joe Subich, W4TV wrote:
> > On Mon, 2012-02-20 at 19:04 -0700, Tod - ID wrote:
> >
> > The important thing is to have a way to assure that when someone
> > measured the same field at the same point with the same type of
> > measurement device they would get the same measurement result.
> > That would allow us to compare measurements between different
> > people even if we did not know the absolute field strength value.
>
> I think simple, repeatable and accurate are a difficult triad. What
> you are talking about is an accurate Field Intensity Meter (FIM) and
> getting stable calibrations with home constructed equipment is not
> going to be easy - let along easy to duplicate. The closest solution
> is to use standard antennas (not simple whips) and calibrate them
> against broadcast signals at known locations and known field strengths.
>
> This will still require separate antennas for 160 and 630 meters and
> separate calibration sources on the appropriate ends of the standard
> broadcast band (due to the antennas).
>
> 73,
>
> ... Joe, W4TV
>
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
It's been many years since I have had to make any AM broadcast field
measurements. I don't recall if the Potomac Instruments, or other, FIMs
go much below 550kHz.
73,
--
Jack, W6NF
Silver Springs, NV
DM09ji
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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