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The "frequency makes a difference" part of measuring inductance of any coil

is the distributed capacitance factor.? This apparent difference in measured

inductance can be used to calculate the amount of distributed capacitance

between windings, but you cannot do anything about it anyway.

When I need to make things come out exactly where I want them I usually

use a signal generator and oscilloscope to measure the resonance point.

• Add up all the frequency determining capacitance in your circuit.
  Select a fixed capacitor of that value.
  
  
• Connect the above capacitance across your inductor.
  
  
• Couple the signal generator across the tuned circuit through a 2.2 pf
  capacitor.
  
  
• Couple the oscilloscope across the inductor through a 2.2 pf capacitor.
  
  
• Tune the signal generator through the expected frequency range while
  looking for a peak on the oscilloscope.

Since you know the C-value and the frequency you can now calculate the
inductance of your coil.? This process includes any distributed capacitance that

is inherent in the inductor windings.?

I have a variable capacitor that has a dial to show capacitance settings in pf.?

With this I can add or subtract capacitance until the inductor resonates at the

exact frequency I want.? This helps when working up a new circuit design.?

The ancient Heathkit LC analyzer is no more.? It was a very useful tool for doing

design work.

Arv? K7HKL
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