Testing the TK Tar Baby

[picowatt]

continued/...
Quote from: picowatt on Today at 05:43:22

    When Q1 is fully on, the drain voltage drops to about +11 volts (with 72 V batt and 11R load).

NOT ACTUALLY.  In fact NOT AT ALL.  When Q1 is FULLY ON both SOURCE AND DRAIN VOLTAGE climb to well in excess of the battery supply source.  The difference is that the Drain voltage is out of synch or out of phase with the battery voltage.



(Speaks for itself...)

[picowatt]

A glimmer of hope:


"I think I see it now.  My question is this.  How does the function generator apply a positive signal to the gate of Q2?  It can't.  Not according to that schematic."



You are correct.  There is never a "positive signal" applied to the GATE of Q2.

Q2 is turned on when the function generator applies a "negative signal" to the SOURCE of Q2.

[Rosemary Ainslie]

Sorry all. I've deleted this post. It seems that I'm now posting on the wrong forum with somewhat monotonous regularity.  Abject apologies.  I'll try and do better.

Regards,
Rosie

Added.
This link answers picowatts earlier insistence that there's a negative signal at the gate of Q2.

http://www.energy-shiftingparadigms.com/index.php/topic,2310.msg2518.html#msg2518

[picowatt]

Sorry all. I've deleted this post. It seems that I'm now posting on the wrong forum with somewhat monotonous regularity.  Abject apologies.  I'll try and do better.


Added.
This link answers picowatts earlier insistence that there's a negative signal at the gate of Q2.

http://www.energy-shiftingparadigms.com/index.php/topic,2310.msg2518.html#msg2518

Your response is incorrect.

As has been stated over and over and over... Q2 is biased on when the FG output applies a negative voltage to the source of Q2.

[Rosemary Ainslie]

Guys - I think picowatt is referring to this response.  As he's NOT inclined to make you fully conversant with the problem - then allow me...

Your response is incorrect.

As has been stated over and over and over... Q2 is biased on when the FG output applies a negative voltage to the source of Q2.

Here's the full response which somewhat detracts from his claim that there's a negative signal at the Gate of Q2. 

And may I add - for edification to the picowatts of this world - IF there is a negative signal as NOW CLAIMED -  applied to the gate of Q2 it would NOT conduct that forward biased (clockwise) current flow (outlined in blue) PRECISELY because that NEGATIVE SIGNAL WOULD REPEL the current discharge from the battery supply.  The battery would not be able to conduct.  The blue trace shows the battery conducting.

I took the trouble to emphasise the argument by highlighting it.

Regards,
Rosemary