Testing the TK Tar Baby

[TinselKoala]

@MH: Can you or anyone else tell me the make and model of the inductance meter used to measure the Ainslie inductances? The information does not seem to be in the papers. In the Video Demo -- which only _relates_ to their claims --  they apparently are using an InsTek 800 series inductance meter, which is a sophisticated instrument that uses multiple frequencies for its measurements. Of course... the more complex the instrument, the greater chances of misuse and misinterpretation.

http://www.gwinstek.com/en/product/productdetail.aspx?pid=39&mid=79&id=188

But as I said before, I am happy to accept the lower inductance values they claim, since that means that Tar Baby's inductances now agree closely with theirs.

Also, in the "references" to the "paper 1" there is listed the manual for a Velleman POWER SUPPLY. Yet this instrument doesn't appear in the paper's list of instruments used. Nor can I find any internet reference to a IsoTech GFG 324 function generator.

There is also this little TidBit at the end of "paper2":

Specific Heat and Ikram Ebrahim for the donation of the
element and his support in supplying exotic resistors as
required.

Yet RA has told us that no special resistors were used. I wonder if Mr. Ebrahim is amenable to discussion of the issues.

[poynt99]

TK,

With your new resonance measurements, I think you are in the ball park. I used all the stated inductance values in the sim, and the results are close to Rosemary's.

You are right about the CSR value, it is of little consequence when for starters one is obtaining a negative VV from the CSR and VBAT trace products.

Have you measured across ONE of your battery's terminals directly with the scope, while all other scope and FG leads are removed? If so, what did you see directly across the ONE battery?

[TinselKoala]

TK,

If the values being used for the inductance/ESR are closer to the values your alternate measurements arrived at, you will have to crank up the FG output to get an accurate measurement of the drop with the FG's 50R.  If they are closer to 1R at 1.5MHz, with your FG at 40volts (amazing!), you should be able to read the divided voltage fairly well.

PW

The Interstate F43 is set to make a sine wave at 2.0 MHz (closer to the actual value of TB's osc freq) (actually 2001.86 kHz on the Philips counter) and 40.0 V p-p "no load". When I then hook a single 1 Ohm 10 Watt power resistor across the FG's output, it drops to 10.4 Volts p-p.

[picowatt]

The Interstate F43 is set to make a sine wave at 2.0 MHz (closer to the actual value of TB's osc freq) (actually 2001.86 kHz on the Philips counter) and 40.0 V p-p "no load". When I then hook a single 1 Ohm 10 Watt power resistor across the FG's output, it drops to 10.4 Volts p-p.

TK,

Is that with the resistor connected directly to the FG terminals or are you using a test lead?

You don't want to be measuring any test lead inductance, so go for right across the terminals.

PW

[fuzzytomcat]

I've done some work on the spreadsheet, incorporating power computations for various CVR reactances. This affects only the absolute magnitude of the power values, not the sign or the shape of the power curve of course.

All "positive" values of shunt inductances still yield NEGATIVE mean power values.

If anyone has a better idea as to the overall impedance of this CVR at 2 MHz please let me know so I can revise the spreadsheet again.

I am happy to use 125 nHy as the total inductance of the CVR based on my resonance measurement instead of the ProsKit meter.

The reactance at 2 MHz will then be
2*pi*f*L == 2(3.142)(2,000,000)(0.000000125) == about 1.57 Ohms,
and the  impedance then is sqrt(1.6^2 + 0.25^2) == about 1.59 Ohms.

With that as the AC impedance at 2 MHz, the mean power shown on TarBaby's scopeshot appears to be about _negative_ 14 Watts.

Right?

Please feel free to check my work -- those of you with the knowledge to do so -- and go over the spreadsheet with a finetooth comb, so that I MAY CORRECT MY ERRORS AND POST CORRECTIONS AS SOON AS POSSIBLE, like a good little scientist should always do. This, after all, is a major reason why RAW DATA and computations are always made available to reviewers of experimental work.

Hi TK,

This is exceptional work you've done the old school way, using a analog scope and some math that obviously you have done this method before !!
http://www.overunity.com/12182/testing-the-tk-tar-baby/dlattach/attach/98153/      ( TBCurrentflow1.xls )

The only thing missing is your Tar Baby "THESIS" of truthfulness, knowledge, hard work, dedication and mathematical skills. 

Cheers,
Fuzzy