[Amps] Measuring Q with an SWR analyzer

[Bill Turner]

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


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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