Partzman, I am assuming that the corrections you calculated up above being small, will also be small in my setup. Do you have enough information to calculate the corrections for one of my datasets?
Also, what effect do you think my casual probing and my non-noninductive resistor might be having on my results? I would like to have some confidence that I am seeing the same effect you have seen but I'm worried that my results may be artifacts, whereas yours may not be, since you are using tighter probing and you have your proper resistor.
I'm happy that the effect can be reproduced even if it's not due to the same cause... but I think it probably is. However this brings up some other issues. Why did you not get similar results when you tried round coils yourself, but only got them with the Golden Mean proportions? Can Itsu reproduce the results using his current probe, wherever placed? And of course we have the issue of whether or not our probing scheme is actually valid for this circuit. At present I am just looking at data, I have not started trying explain it or to find errors if they are there.
I've got to say though, that I haven't had this much fun in the lab in quite some time! 
TK, OK, looking at your post #141, the voltage across your sense resistor appears to be ~71.2v rms and with a phase angle of ~83 degrees so, you would subtract .0712 *cos(83) = 8.7mv rms from your 11.9v rms input leaving a net input of 11.89v rms. Assuming you would have approximately the same outside capacitive coupling as I appear to have, increase the sensed current by 5% to 75ma rms. Your corrected Pin is now 11.89*.075*cos(83) = 109mw for a new COP = 2.41 vs 2.58. I prefer to use the recommended RF style measurement technique with the probe tip and spring ground right at the sense resistor with all other grounds connected directly at the bottom of R2. Moving your probes around while taking measurements should give you an indication of any circuit to probe interaction. The inductive load resistor could lead to erroneously high COPs depending on how inductive it is at the operating frequency. You might try to series resonate the load resistor with a known capacitor to profile it's inductance. I used this simple test to qualify the Caddock non-inductive film resistors I use and basically found insignificant inductance up to ~10MHz. The round coil tests I ran that never provided a COP>1 were using 3-5 stacked coil configurations with variations. I have never tried 2 coils in a round configuration. I did have success with triangular, square and rectangular shapes plus coils wound on toroidal forms but all in 3 coils or more. I will be pleasantly surprised if Itsu can get a COP>1 at his low operating frequency. The lowest frequency I have achieved COP>1 is at ~650kHz using 3 coil devices. The goal is to reach a COP~1.5 to 2.0 at 100kHz or below. If this is reached, a self runner can be realized IMO. I really glad to hear you are having fun with this  ! Pm Edit: I should comment that I have never tried using coils in the configuration that you TK, TM, and Itsu, are using in the Tesla wound configuration- Hmmmm!
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Topic: Investigating "anomalies" in Bifilar coils (Read 201338 times)
