Do you mean your answer on Schmitt trigger? I skimmed your answer but found it too long for a morning read. Perhaps I can check it out later. I did not learn Schmitt trigger in my EE diploma, so I am interested to remedy it. So you see earlier I assembled a Schmitt trigger triangle wave gen and I will use it later for the tunnel diode experiment.

@Circuitfantasist Well, I did also once use Turbo Prolog in my IBM PC days. Actually the python program I am writing now uses some of the programming ideas, such as "declarative programming style (not procedural or OO), using predicate logic etc, .. In the deleted CD chat, I remember towards the end, I told you that I will use Occam's Razor style to answer my own question of the tunnel diode's missing NDR plot. You see I am still working on it. :)

BTW, I do thinkg Turbo Pascal good for small programming projects.

About the R1 R2 notation. If you goolge opAmp images, you whould find how many images are using Rf, Rg, and Rin, and how many using R1, R2. As I often say, you are chasing your audiences away, if they don't know your notation, and no diagrams along side to help to figure out, ...

"Rf" is misleading since it is not only the resistor constituting the feedback network; both resistors make it (they form a voltage divider driven from the side of the output). Maybe "Rout" is more correct...

I prefer to use "R1" for the input resistor (between the source and "-" input) and "R2" for the output resistor (between the op-amp output and "-" input). Of course, I always use drawings in my explanations but here it is not convenient.

I am discussing now another relatedgreat idea with my students - the so-called "sense amplifier"...

The matplotlib is very newbie friendly. I just spent 10 minutes skimming the beginners guide, read the demo program, and only made a couple to trials and errors and successfully drew the following Tunnel Diode 2SB4B I-V Curve, using the crude manual measurements I listed in my question.

Now I am coming back to v2.0 of the tunnel diode I-V curve plotting proposal. tunneldiode.blogspot.com/2020/12/…. As I said earlier, this v2.0 hardware will use (1) 12-bit current sensor, (2) 12-bit ADC. Both toys arrived this afternoon, just in time to start playing. :)

I think only Edison has worked so hard... well, me too:) Here's my new blog post and CD.