To: <amps@contesting.com>
>> Date: Mon, 25 May 1998 10:44:01 -0500
>> From: Jon Ogden <jono@webspun.com>
>
>> >I know that this isn't much of a measurement, but do you think it would
>> >be a worthwhile indication, Tom?
>
>That works well here.
>
>> Well, given I don't have an MFJ-259, that would be difficult.
>
>> My thought was to place a cap in parallel with the resistor and then
>> measure the resonance with a dip meter. From there, one can calculate L.
>
>Dip meters tell you nothing about impedance. Wrong "tool", and not
>much of a tool at the very best. That's why they fell out of the
>mainstream long ago.
>
During the grate suppressor debate, Mr. Rauch stated that the highest
grid resonance frequency was obtained when the grid was directly
connected to chassis-gnd. However, a dipmeter indicated that a slightly
higher resonance could be obtained by grounding the grid through a
capacitor, as is done in the Collins 30L-1. Presumably, the neg.
reactance in the C cancels some of the pos. reactance in the tube's
internal leads. It makes sense to me, and the dipmeter confirms it.
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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