Joel,
Thank you for that explanation.
I was puzzled because neither in the text nor in the block diagram of
the test setup is there any mention of a tuner at the signal generator
end, and I can only see one tuner being used for the back-to-back tests
in the Figure 4 photograph.
I see some practical difficulties in adjusting the two tuners: the tuner
at the generator end will need to be adjusted whilst watching the
microvoltmeter at the load end 95ft away; and because the settings of
the two tuners will be interdependent it will necessary to iterate the
adjustments several times - not easy when they are 95ft apart.
73,
Steve G3TXQ
On 27/01/2012 17:17, Joel Hallas wrote:
> Steve,
>
> Good questions, and this goes back some time, as I remember it, we had the
> line going into a 9:1 balun at each end. On the distant end, where the
> microwattmeter was, we had the 50 ohm termination of the wattmeter. At the
> generator end, on the coax side of the balun, we had a pi-network tuner (my
> old 100 W tentec, appropriate for this forum). For each test at each
> frequency, I adjusted the tuner for maximum response at the far end. My
> conclusion is that the line was thus matched to the generator at each test
> point. Whatever the transformed impedance of the far end (meter load) was at
> the generator was matched for maximum power transfer to the system at
> whatever impedance it was.
>
> I hope that makes sense, and makes you more comfortable with our technique?
>
> Regards, Joel Hallas
> Westport, CT
>
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