[Amps] Measuring tank coil inductance

[Radio WC6W]

> I've been trying to find a good
> method to measure the inductance of large coils made out of
> tubing

<snip>

Hi Vic,
  I have an ancient HP 4260A bridge which suffices for most measurements.

  However, for tank coils, I use a Time Constant circuit which is a variation of the design published in the Jan. 1992, 73 Magazine, pp 38 & 40.

  I up spec'ed to 74AC parts and ran the current up to realize a 1-50 uH range.
  
  There is a similar design in the ARRL Handbook in the mid-2000's.  This one has a zero adjust to fix the ground offset caused by the high currents employed.  A better approach is to use a separate package for the output inverter.

  Very useful for measuring tank coils in situ.

73 & Good morning,
  Marv WC6W

P.S. -- I have a PDF of the 73 article that I can send direct if you wish.  Not sure if I ever drew up my version for real (orcad).




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