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John M0GLN · 24th Feb 2009, 3:59 pm

Well I got around to doing the tests as recommended by Oldtimer74 and OErjan_S, using a 4t coil for the 'scope and a 4t coil with 39Ω series resistor for sig' gen', I tested a home wound coil, first with a 100pF and then with a 390pf capacitor in parallel with the coil under test, the resonance peak was sharp on the 'scope and very easy to determine, when I put the capacity and frequency values into the on line calculator I got results of 151μH and 147μH, as a further check I put the coil details, diameter, length and turns into another on line calculator and it gave me an approximate inductance value of 144μH, not bad results for a quick check, certainly an excellent way of doing it,

Thanks

John

24th Feb 2009, 3:59 pm	#18
John M0GLN Octode Join Date: Jan 2004 Location: Southport, Merseyside, UK. Posts: 1,156	Re: Measuring Resonant Frequency Well I got around to doing the tests as recommended by Oldtimer74 and OErjan_S, using a 4t coil for the 'scope and a 4t coil with 39Ω series resistor for sig' gen', I tested a home wound coil, first with a 100pF and then with a 390pf capacitor in parallel with the coil under test, the resonance peak was sharp on the 'scope and very easy to determine, when I put the capacity and frequency values into the on line calculator I got results of 151μH and 147μH, as a further check I put the coil details, diameter, length and turns into another on line calculator and it gave me an approximate inductance value of 144μH, not bad results for a quick check, certainly an excellent way of doing it, Thanks John