Bill Turner wrote:
(snip)
> Here's my procedure:
>
> 1. I tacked a 2200 ohm resistor across C1 to simulate the load
> presented by the 8877.
>
> 2. I connected the MFJ-259 SWR analyzer across C2 and set its
> frequency to 13.31 Mhz.
>
> 3. I adjusted C1 and C2 for a 1:1 SWR as shown on the meter.
>
> 4. I tuned the analyzer lower in frequency until the SWR read 2:1 and
> made note of the frequency, 12.844 Mhz.
>
> 5. I tuned the analyzer higher in frequency until the SWR again read
> 2:1, 13.867 Mhz.
>
> 6. I subtracted the low frequency from the high frequency to get the
> 2:1 SWR bandwidth, 1.023 Mhz.
>
> 7. I divided the center frequency (actually the numeric average of
> the high and low) by the 2:1 bandwidth to get a Q of 13.06. I then
> applied a correction factor (for the accuracy of the SWR analyzer) of
> .9188 to get a Q of 12.
Sounds pretty reasonable to me. One detail: You get a slightly more
accurate center frequency by taking the square root of the product of
the two -3db frequencies. This is the geometric mean, rather than the
average. But at a Q of 12, it makes only a tiny difference.
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