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Old June 10th 06, 11:11 AM posted to rec.radio.amateur.homebrew
Roy Lewallen
 
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Default Identifying Surplus Toroid Material

Alan Peake wrote:

Good method. I have done that before but my current RF sig gen doesn't
have very good output level regulation, nor is the output adjustable -
it's only a one-transistor sig gen after all
They wouldn't let me take my H-P with me when I retired ]


Neither of those should be a problem. The absolute level isn't
important, and the amount you have to adjust the frequency for a single
measurement is small -- for inductors of reasonable Q, anyway -- so the
level probably won't change much over that small range unless the level
stability is extraordinarily bad.

I've got a one-FET homebrew oscillator I made a long time ago with an
extra transistor or two for a crude ALC that keeps it reasonably flat
over the whole HF range. But you shouldn't need an ALC for most Q
measurements.

Roy Lewallen, W7EL