Hi Electrician,

I calculated [Rth] 3.1 as well.

 

Also - Just checked using simulation - values agree with those calculated.

 

Reversing the input sensing for the VCCs from that shown in the circuit gives Rth=1.9 ohm - per Ratch's declared value.

Rather counter-intuitively (i.e. for me anyway - given the presence of the VCCS), the Thevenin equivalent holds valid for any applied load. This was verified by Ratch for the polarity he used for the VCCS control. In fact it holds true for either polarity used.

 

Here are the simulation circuits and results for a 1 ohm load

 

The Electrician,

Do you agree?

Yes.

Ratch