G3RZP wrote:
> I didn't think we could find a subject with so much agreement between
> everybody!
>
> This suggests the inputs are technically correct................
>
>
> I have this nasty idea that I'm going to have to build a GDO.
>
> BUT is it possible to test using a resistor plate to ground (of same
> load
> resistance as the plate wants to see), no DC, a VTVM with a good RF
> probe at
> the plate and feed in at say 5 watts from the antenna end and check
> that the
> volts at the plate are correct when tuned up? Do it on all bands of
> course.
>
> Not as easy as dipping the RFC with a gdo, but easier than building a
> GDO to
> do the job.
>
> Comments?
>
> 73
>
> Peter G3RZP
>
Or test using a resistor plate to ground, no DC, RFC not connected or
maybe even not present. Measure return loss at antenna port, tune
circuit for desired frequency, connect RFC. The only thing you should
see is a change in the tune capacitor setting, especially at the lower
bands. Could be done with an antenna analyser, TX and SWR meter or (and
that is by far the easiest way to do it) with a Network Analyser. Works
fine for me.
Gerard, MoAIU / AA3ES
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