>Tom, you say
>
>>Or a capacitive divider also works. That's what nearly EVERY bridge
>>made does.
>
>Isn't the Bird slug the same? There's mutual inductance between the
>centre of the coax line and the slug, and similarly there's capacitance
>between the line and the slug.
>
>The analysis of the Bird, and the old Monimatch for that matter, is I
>believe, that of a Maxwell Bridge.
>
>The matter of accuracy is very pertinent: if the device had a digital
>readout instead of an analogue meter, I'd bet that there's a lot of
>people would believe it to the 4th decimal place!
>
>73
>
>peter G3RZP
>
Amen, Peter. (distant laughter).
- I propose a simple test to see if Rich is guilty of wanton and
reckless technoblathering:
1. Measure the forward and reflected power on a transmission line with
roughly a three to one swr.
2. Subtract the measured reflected power from the measured forward
power.
3. Add a quarter wavelength of coax between the wattmeter and the load.
4. Subtract the measured reflected power from the measured forward power.
5. Compare the result in #2 with the result in #4.
Another test is to compare the above power measurements to that obtained
with a bomb-calorimetric wattmeter.
R. L. Measures, 805-386-3734, AG6K
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