Testing the TK Tar Baby

[MileHigh]

ETA: Wait, are we counting the batteries the same way? I assumed you meant from the most negative pole, to the most positive pole, of the whole stack. That's where I have the probe, across the whole 36 nominal volts.

Yes indeed, that's what I mean.

Put it this way:  There is an analogy with being faked out by superimposed AC on the batteries and when someone runs a pulse motor and sees that the battery voltage is creeping up because of a warming up of the electrolyte or whatever.  That MIB response team must endure scenes just like firemen and false alarms.  Eventually the inner thighs get chapped from all of that riding down the MIB pole.

If I had just a measly $0.05 for every time somebody got excited by seeing a rise in battery voltage I would be in piggy bank heaven.

[TinselKoala]

Oh, this burns me up.
My recent findings are these:

1. Even accepting the "related as +- 5 Watts" as meaning 5 watts of power dissipated at the load resistor, I've calculated that their batteries would last a _long time_, months maybe, before dropping below 12 volts, providing that measly level of power.

2. TarBaby can't heat a load substantially unless some of the mosfets are turning at least partially ON during the oscillations and/or the antiphase non-oscillating periods. When I apply sufficient current to match their "5 Watt" value, I get beaucoup load heating.. but my mosfets are partially on, some of them, and fully on, others.

3. For the "massive" load heating of their resistor to far above the boiling point of water.... their own scope traces and data show that they TOO are turning mosfets fully on during this part of their demonstration, during the antiphase, non-oscillation portion of the waveform cycle.

4. Argentina was boring, although the weather was nice there in the late 40s and early 50s. But America is the Land of Opportunity, and there are still a few good German restaurants in South Texas if you know where to look. And Shiner Bock ....  Sieg p'suffa !!

[TinselKoala]

Time is 1824, Load is at 235 F and still climbing. I'm trying to maintain that 700 mA level on the DMM; it requires tweaking the FG amplitude once in a while, mostly due to the temperature of Q1, I think.
Batt voltage under the circuit load is 35.1 volts. Looks like I'm not recharging.

[TinselKoala]

MH said, "Poynt believed that Rosemary had her battery probe in the wrong place and the AC would not be manifested if your probe was right on the battery terminal itself. "

Actually I think that's probably correct. If I get rid of all stray wiring and use as short as possible ground lead on the probe itself, I can cut the apparent amplitude of the oscs on the battery trace by about 2/3. In the ideal world of circuit sims, I'm sure they would go away completely, and in reality too, if you could put your scope and probe inside the battery case.

However.... there are those pesky LED/inductor combos, right at the battery terminal, showing us something... at the very least they are showing us that there is enough power in the AC oscs, not being metered, to light up a few LEDs.

[TinselKoala]

Ok... so what am I doing wrong? Why aren't my batteries recharging? Tar Baby has the same type and number of mosfets, has the same value (within tolerance) shunt CVR, has the same gate drive settings IN BOTH MODES, oscillating small heat and big load heating modes both, has the same scope traces at the same points, has the same oscillation frequency or exactly twice that frequency....  has the AC component with power in it.... everything except battery recharging.

And the evidence that the NERD RATs have presented to indicate battery recharging is, first, the no-load voltage "alleged" to be at or over 12 volts on the batteries after much use, and second, the spreadsheet numerical integrations and comparisons of scope values from improperly adjusted and employed oscilloscopes. And this by someone who thinks that a Joule is a Watt per Second and that you can put 25.6 million Joules into a liter of water in a hundred minutes without having to call the Fire Brigade.


Why aren't my batteries recharging? I don't think anyone, at this point, can claim that there are significant differences between Tar Baby and NERD. If there are, please describe them and I will be happy to correct them if I can.




Damn... I knew I should have bought that white pegboard.