Rosemary:

QuoteThat's probably on the money.  I can ONLY manage simple schematics - at best.  But that 'schematic' as he refers to it - is NOT a schematic.  It's 'taking liberties with conventional schematics' - as written.  I'll take the trouble to post this again.  It's important that you get your head around this.  I'll also highlight it when I get to my moderated thread - in about 2 weeks from now.  NOTA BENE.  The source leg of Q2 is not connected to the circuit's source rail (negative battery terminal as Poynty puts it).  This can be readily shown.  And I'll do so. Just bear this in mind and note this in the context of picowatt's denial of this fact.  I shall enjoy showing him that he is, again, 'erroring'.

Just draw up a conventional schematic.  There is absolutely no such thing as "taking liberties" with a schematic diagram.

What's your problem?  Are you too lazy to draw up a schematic?  Can't you just modify or mark up one of the existing schematics to get your point across?

At the same time, can you show us EXACTLY how the current is supposed to flow by indicating that on a schematic?  Your verbal description will simply not cut it, ever.  One more time, what's your problem with doing this?  Are you too lazy to do it?

Think about this:  You have been "doing battle" here for a few months, and yet you can't take one hour of your time to make schematic drawings to back up your points?  A picture is worth a thousand words and when your words are sliced and diced into a salad it makes comprehending you that much more difficult.

And please, for the love of God, STOP calling a battery negative terminal the "source rail."  You are the only person in the world that says that.  Get with the program and start using the proper terminology.

MileHigh

And guys,
Again.  Where I reference a training in psychology - NOTA BENE

Quote from: TinselKoala on May 02, 2012, 11:00:40 PM

Psychology is indeed a science; more correctly, several distinct sciences are bundled under the generic appellation "psychology". Many psychologists know a lot more about research methods, experimental design, and statistical analyses than many physicists do. And when we begin to discuss formal models of cognitive processes like visual pattern recognition.... we are up against a hard science, indeed, involving lots of multidisciplinary knowledge.

Note the use of the word 'WE'. 

I rest my case.
Rosemary

Quote from: MileHigh on May 02, 2012, 11:12:58 PM
Hey TK:

The second clip was pretty cool with the grounding example.  As PW stated, it's an art to manage your grounds.

I have a wish list item for an analog scope were both channels are completely isolated and powered by separate isolation transformers so you can put your probes anywhere.  I suppose that complicates matters when you need to drive the analog deflection amplifiers and you need some kind of voltage reference to between the channels and the amplifier to do that.  Perhaps an optical link between your isolated scpe channels and your deflection amplifiers?  lol  An analog scope with a hidden optical-digital data pathway that is so high in bandwidth that it looks exactly like an analog scope.

Anyway, I want to focus on the first clip.  You showed how the 10.3-ohm resistor has roughly 170 mA of DC current going through it with a relatively low AC waveform superimposed on top of it.  That AC waveform was quite similar to he waveform observed across the CVR.  And you showed how the multimeter was in agreement showing about 170 mA of DC current flowing through the circuit.  This is quite conclusive proof that current is flowing right through the function generator, and it backs up what you demonstrated in your second clip.

I am assuming that your "negative terminal" of the "function generator equivalent" circuit is connected before the CVR.  i.e.; You have build the "corrected" circuit where the CVR shows all of the current passing though the circuit.

What I am trying to understand is this:  The waveform across the 10.3-ohm resistor shows that the current though the "function generator equivalent" and the source pins of the Q2 array are mostly DC with a smaller AC component.  However, when you look at the 0.2 ohm CVR, you see what appears to be nearly all AC.  Aren't the 10.3-ohm resistor and the CVR in the same loop?  Is it possible that it's related to the Q2 array gates and the assumption that there is AC power coupled through the gate capacitance?  Note that the Q2 array AC power will tend to flow through the CVR because it is a much lower impedance path than the 10.3-ohm resistor.

Perhaps I am missing something or you can explain it?

Thanks,

MileHigh

MH,

When the bias source (FG, etc) applies a negative voltage to the source of Q2:

With regard to DC, all DC (bias) current flows through the source of Q2, the FG (or equivalent bias source) and the CSR (if the bias source is connected to the CSR instaed of battery ground).  The low value of the CSR will only drop 50mV or less depending on the DC bias current and the CSR value, so this amount of DC offset at the CSR may be difficult to see at the typical scope settings.  If the oscillation were squelched and/or the scope DC gain increased, the DC bias current would be more apparent at the CSR.

For AC, take the FIG 1 schematic of the first paper and draw in four capacitors.  One cap from drain to gate and one cap from gate to source on both Q1 and Q2.  For the Q2 array, the value of the drain to gate capacitor is 1000pF.  The gate to source capacitor is 11,200pF.  For Q1 the values would be 250pF and 2800pF (all values approximate).

It will now be apparent that the bias source (and 10R3 or FG's 50R) in the source leg of Q2 is heavily bypassed for AC at the freq of osc via the MOSFET intrinsic capacitances, Coss and Ciss.  Most of the AC current will therefore bypass the bias source and flow through the MOSFET capacitances to the CSR.

I hope I understood your question, let me know if this helps.

PW

Hello Stefan,

Quote from: hartiberlin on May 02, 2012, 06:27:16 PM
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

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

Rosemary:

QuoteJust bear in mind that I KNOW that current is flowing through the function generator.  How else could it apply a voltage at the MOSFET gate leg?

First of all, you make a statement that kind of suggests that current is flowing through a MOSFET gate, yet again.  Will you ever learn?  I somehow doubt that you are discussing the charging of the gate capacitance here.

More importantly, you are contradicting yourself.  You also contradicted yourself about posting your demo video clip from last year.  It makes people reading you wonder if you are becoming mentally imbalanced.  My advice to you after your dim bulb test fails is to walk away and simply forget this whole project of yours.

MileHigh