On Thu, 10 Jan 2008 18:48:00 GMT, ehsjr
wrote:


The whole thing, at this stage, has to be outdoors - and that
includes the test equipment. The inductance measurement changes
with temperature, AIRC, but I don't know yet how much of that,
if any, is test equipment error. Using the frequency change
approach vs delta L makes a wider input, and small changes
in level were easier to see. I hadn't thought of pulsing a
current and measuring V.

I may have to jury rig something for testing to bring the
equipment inside where the temperature remains the same.

Ed

As a test, could you not bring everything into the kitchen? Measure
the inductance at room temperature, then put the coil in the fridge,
and watch for inductance changes as it cools.



--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
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