ORIGINAL MESSAGE:
At 01:52 AM 1/5/2006, Peter Chadwick wrote:
>An easier method would be to feed a signal in and measure the volts
>across the load resistor with a RF voltmeter (VTVM!) or 'scope or
>whatever, and measure the frequencies where the volts has dropped to
>0.707 of the volts at resonance.
>
>73
>
>Peter G3RZP
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Good idea. I also considered building a pi net with known Q and
measuring the SWR bandwidth at some specific SWR such as 2:1 and then
deriving a formula from that. Presumably it would be scalable to any
frequency. I realize the accuracy of my equipment (MFJ analyzer) is
not the greatest, but a close approximation should suffice.
Earlier comment about keeping the measured bandwidth small to reduce
the effect of asymmetry is noted.
73, Bill W6WRT
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