Testing the TK Tar Baby

[TinselKoala]

@ReFried:

Thanks for stepping in!

And also thanks for that reference to the D-K effect. I've often thought the same, myself, with reference to our main subject.

Of course.... if one does not believe in objective measures of competency or knowledge, one is all the more subject to the D-K effect. When I make a "C" on a test, I know that I'm probably of average ability. When somebody else makes a "C" on a test, she thinks that the test was unfair, that the textbooks are wrong, and that the professor is FOS.


Welcome to Lake Woebegone, where all the children are above average.

[picowatt]

60 uf sounds more like it. One or 5 helps but there is still noticeable ripple.  But I can only get to about 40 uF with all my blue RIFAs.

TK,

I believe some time ago I suggested something like 220uF electro with smaller caps paralleled to decouple the electros internal L.  Dig out an old PC supply and grab a 100-470uF or whatever for LF, and then parallel a pretty blue and one of your .1 glass.  But yeah, beat me up, I did say one of each in your picture..

PW

[poynt99]

60 uf sounds more like it. One or 5 helps but there is still noticeable ripple.  But I can only get to about 40 uF with all my blue RIFAs.

10uF was sufficient across a single battery, that's why I multiplied by 6 to get 60uF across all 6 batteries.

In other words, for the single battery test if you do it, you'll only need 10uF or so to cause a significant change in the computed power, but of course the more the better.

[picowatt]

PW,

This is for you, as requested.

Note; I did not add any inductance. It oscillates nicely with the filtering across all the batteries.

Also note that 3.3W x 4 = 13.2W, precisely the same value obtained by using the power probe on one battery and multiplying by 6x.

99,

Thanks poynt.  I envy your sim work.  Gotta' get me some.  What software/version do you use?

I understand what you are saying regarding just decoupling one battery and then multiplying, and I know I will accept a measurement taken that way.  There is just something a bit more "magical" when one can demonstrate a totally different measurement taken at opposite ends of an ordinary wire.  A wire is not always just a wire.

PW

[TinselKoala]

@PW:
You said, "I think all the work you have put into this will have more value for readers here and elsewhere than as it just pertains to this circuit. "

Thanks... I hope that the main benefit will be in the information about the use of the oscilloscope to make actual measurements rather than pretty colored lines.

I've seen a lot of scope displays on these unconventional science (sic) forums that make it clear that scoposcopy is a lost art, and that people need numbers in boxes these days, that the basic operation of the scope is often misunderstood, and that artefacts are almost never considered.

The shots below are typical of the Ainslie shots from the "old days" and show nothing more than aliasing and poor triggering, yet they were presented as representative of overunity performance.

(NOTE also the description in the figure caption: Channel 1 is described as the "integral of voltage across the current sensing resistor (Rshunt)." But it is not an integral at all. The LeCroy can only display a single math trace, and that's being used to display the product of 1 and 2. Trace 1 is not an integral, it probably is just the raw voltage drop across the CVR.)