I have another problem with the Owon scope it has pulsed noise on lower sensitivity, looks like switched supply noise, maybe some caps drying out. So back to using the hantek. So tonight i re did all the tests but this time at 100khz intervals. This time i used the 2 Chanel's to match the current and voltage phases, and once that alignment was done, i then used just 1 channel to get each value to reduce any chance of a second Chanel causing inaccuracy's. I also used the pk-pk voltage, all measurements were take with respect to the Sig gen ground, so i had to subtract LCv from the Current waveform to isolate just current, i converted pk-pk to amplitude (/2) i then multiplied by 0.7071 to get Rms and worked my Pin, Pout & COP from there. I employed the use of a spread sheet to do all the maths Load=516 Ohm NIR=10 Ohm The only problem i can see here is that because i am only using 1 probe to measure each parameter i am hoping that the phase did not shift when i removed the 2 back to back probes during inital phase alignment. I'm still getting high value COPs are they too good to be true. Something i am unable to get my head round, i must be dissipating energy in my NIR If i take 400KHz for example then my voltage across NIR 10 Ohm is 3.27-1.96 = 1.31/2 =0.655 * 0.7071 =0.4631505 Vrms P=V^2/R P=21.45mW So if i have this correct and i am dissipating 21.45mW in my NIR then how can i have a Pout of 31.48mW & a Pin of 32mW? Something is very wrong here somewhere
« Last Edit: 2015-02-26, 21:58:25 by Peterae »
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