>> The input Z of a tube in g-g config. varies greatly, depending on drive
>>level. When drive level is low, input Z is high. When the drive is
>>high, the input Z is low. Thus, a noise bridge, which uses uses a
>>miniscule level of RF, provides no clue.
>Everybody claims this, but I haven't seen it. The input impedance does
>NOT vary with input power. I have the exact same match applying 100
>watts as I do 5. My SWR does not change.
You are talking about measuring swr with a tuned circuit/flywheel at the
cathode. Cathode impedance, this is not. You must measure direct into
the cathode? . . One problem with a noise bridge is that the power is
in the microwatt range. .
>Also, with a solid state rig, how can I apply full drive with a bad
Make C1 equal to 25 ohms of Xc (450pF @ 14MHz). Vary L1 and C2 until you
obtain a 1.2 or better swr. The radio should then be able to deliver
R. L. Measures, 805-386-3734, AG6K
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