Testing the TK Tar Baby

[picowatt]

I am no electronics engineer but I was under the impression that a field effect transistor needs only voltage to trigger the main.  Usually the gate has an rc network attached to make sure the fet doesn't miss fire.  The signal generator needs to supply enough current to overcome the rc network filtering and satisfy the gate capacitance.

Sparks,

You are correct for the most part.

All FET gates act as capacitors, and once charged, only a very small gate leakage current is drawn from the gate.  So, as the FET is turnng on, i.e., as its gate capacitance is being charged, current is drawn as required to charge the gate capacitance.  Once charged, very little current (typically picoamps/nanoamps) is required to keep the FET gate charged.

For high speed switching operations with power FET's, which have a fairly large gate capacitance, charging and discharging the gate capacitance rapidly can require very large currents.  Typically a driver IC is used to drive the gate which has a buffer stage capable of supplying the large currents needed to rapidly charge/discharge the gate capacitance for high speed turn on/turn off.

Small signal FET's have a much lower gate capacitance and require much less current to charge their gates, but even here, the gate capacitance can not be ignored, particularly in high frequency amplifier circuits.

It can be easiy demonstrated that it is possible to charge the gate of a FET and then disconnect the gate and the device will remain on as the gate capacitance slowly discharges.

Typically the gate capacitance is specified on data sheets as "input capacitance" and abbreviated as "Ciss" (input Capacitance with drain shorted to source).  Ciss is therefore considered to be the sum of Cgs (gate to source capacitance) and Cgd (gate to drain capacitance), with Cgs typically the larger of the two.

PW
 

[TinselKoala]

Yes, all of that is right.
(Except that I still believe that she is discussing the Drain signal not what she calls the "batt" signal,  in that blog post.)

However I am trying to illustrate a solid point, and that is that the DC current to turn on the gate of the mosfet is tiny and is NOT the current that we are measuring from the bias source in the Tar Baby or by extension in the NERD device.

All of this is in conjunction with trying to get her to understand that the FG or other bias source DOES act in series with the main battery, and the gate connections are in "parallel" to the source-drain path, and that the DC current involving the gate is a minuscule portion, probably not even measurable at the current instrument settings.

I showed in my video how just touching the gate pin even through a 1megohm resistor can turn the transistor on, and also I demonstrated how the transistor stays on even when the gate pin is totally disconnected from anything, and that the gate charge must be "sourced" away for the mosfet to turn off. All of this means that the DC current to the gate is small and once the gate is full this current ceases to flow, and these are the points that Ainslie needs to understand in order to realize that the DC current in the bias is NOT flowing through the gate at all but is in series with the main battery and is flowing through the drain-source path and the load.

Certainly the gate-source and gate-drain capacitances will also pass the AC current that is sitting on top of the larger DC component of the negative bias being sent to the Q1 sources (and positive to their gates.) I'm talking about strictly the DC case here, for pedagogical purposes, even though I know it's hopeless.

[picowatt]

Yes, all of that is right.
(Except that I still believe that she is discussing the Drain signal not what she calls the "batt" signal,  in that blog post.)

However I am trying to illustrate a solid point, and that is that the DC current to turn on the gate of the mosfet is tiny and is NOT the current that we are measuring from the bias source in the Tar Baby or by extension in the NERD device.

All of this is in conjunction with trying to get her to understand that the FG or other bias source DOES act in series with the main battery, and the gate connections are in "parallel" to the source-drain path, and that the DC current involving the gate is a minuscule portion, probably not even measurable at the current instrument settings.

I showed in my video how just touching the gate pin even through a 1megohm resistor can turn the transistor on, and also I demonstrated how the transistor stays on even when the gate pin is totally disconnected from anything, and that the gate charge must be "sourced" away for the mosfet to turn off. All of this means that the DC current to the gate is small and once the gate is full this current ceases to flow, and these are the points that Ainslie needs to understand in order to realize that the DC current in the bias is NOT flowing through the gate at all but is in series with the main battery and is flowing through the drain-source path and the load.

Certainly the gate-source and gate-drain capacitances will also pass the AC current that is sitting on top of the larger DC component of the negative bias being sent to the Q1 sources (and positive to their gates.) I'm talking about strictly the DC case here, for pedagogical purposes, even though I know it's hopeless.

TK,

I would have drawn the switch as a center off SPDT switch with the "throws" connected to batt+ and batt-.  The pole would then go to a normally centered ammeter and from the ammeter to the gate. 

This way both turn on and turn off meter "bump" and the disconnected gate gate scenario can be demonstrated.

Difficult to discuss without a "spoiler" alert!

But I do know what you are trying to prove...

PW

[TinselKoala]

Hi Rosemary,
I think it is better to make some new experiment, than to rant here all the time.
Just do the experiments and prove TK wrong if you can do this with your setup...
And show it in videos as he is showing it.
I got again some complains of some users that you only rant here and don´t do the required
experiments.

Regards, Stefan

Hello Stefan,Your point is taken.  I'll try and confine my comments to direct denials when I see 'spin'.  Otherwise I'll stay out of it.  Actually I hope, eventually, to get enough strength of purpose to stop commenting at all on this thread at all. 

Regards,
Rosemary

You probably think that got you off the hook, don't you. But you still have these errors to account for, since you always correct your errors.

This instrument listed in your "paper":
IsoTech GFG324.... what is it? Error... or not? If not, where is there any information about this FG on the internet? If error... you have not corrected it. Here is your chance.

This statement:

Correctly it is one Joule per second - but since 1 watt = 1 Joule and since 1 Joule = 1 watt per second - then AS I'VE EXPLAINED EARLIER - the terms are INTERCHANGEABLE. Which is ALSO explained in WIKI.

http://www.overunity.com/11675/another-small-breakthrough-on-our-nerd-technology/600/
Right? Or wrong? Perhaps you should read the WIKI again.

This calculation and conclusion based on it:

In any event it has now been running for 67 hours.  Therefore it's dissipated 10 x 60 x 60 x 67 = 2 412 000 watts. Sorry I've overstated this.  It's been running since Friday 10.30am therefore only 54 hours.  Therefore 1 944 000 watts dissipated. It's rated capacity is 60 ah's = 60 x 60 x 6 batteries @ 12 volts each = 1 296 000 watts. Technically it's already exceeded its watt hour rating at absolutely NO EVIDENT LOSS OF POTENTIAL DIFFERENCE.

http://newlightondarkenergy.blogspot.com/2011/07/134-more-results-this-is-getting-bit.html
Right? Or wrong? Do the Math? Perhaps you should... CHECK YOUR WORK when you get an answer that seems unusual, rather than assuming automatically that it "proves" your "thesis". You certainly have "overstated this". And note well: the errors in the item above contribute to your errors in this item.

This is the calibre of output from Ainslie. Again and again she has illustrated that she does not grasp fundamental concepts of power and energy, that she makes conceptual and calculation errors again and again, and refuses to correct her mistakes or retract the conclusions based on them. It seems impossible for her to make a single statement without making some kind of error, personal insult, veiled threat, or paranoid fantasy-borne accusation.

[TinselKoala]

TK,

I would have drawn the switch as a center off SPDT switch with the "throws" connected to batt+ and batt-.  The pole would then go to a normally centered ammeter and from the ammeter to the gate. 

This way both turn on and turn off meter "bump" and the disconnected gate gate scenario can be demonstrated.

Difficult to discuss without a "spoiler" alert!

But I do know what you are trying to prove...

PW

Yes, that would be a good illustration. More complicated than just the present situation though.  (Darn that Ben Franklin anyhow. It's hard enough to explain this stuff without having to think about how a negative voltage supplying electrons "sources away" the positive charge that keeps the mosfet gate ON......       )

You know, I don't have a single center-zero ammeter in the house, I don't think.

The closest I can come is the Fluke 83 DMM in relative mode, it will display a center-zero bargraph. But its sample rate is too slow probably. Maybe I can figure out a way to show the tiny surges and their directions effectively on the RM503.

I intend to re-do the "mosfets how do they work chapter 2" video and I'll try to incorporate your suggestion. I sort of did it that way the first time through but not quite elegantly enough.

Any word on that slow boat? It must be coming from a lot further away than China.  Alpha Ophiuchi 8, maybe?