Transistor HFE - IC curve tracer?

Yes Locky Z's tracer makes that super easy -- because it's a software input, and software is quite flexible. Either before, or after, running a trace on the Locky Z, you can move your mouse to the plot window and click the Y-axis (or the X-axis). Then his software pops up a dialog window that lets you specify an Axis-min and Axis-max of your own choosing.

For the plot attached to post #118 of this thread, I clicked the X axis and chose (min=0, max=120mA) then I clicked the Y axis and chose (min=200, max=450). The transistor's datasheet predicted that Beta would swing between 70 and 220, but the physical transistor itself had a Beta which stayed in the narrower range (350 < Beta < 410).
 
Add a variable emitter degeneration to the circuit ?

The MPS transistor with and without emitter degeneration:

Looks like it linearizes the left side of the mountain top only, the right side even suffers a bit.

Typo in the pictures 😵

mps_deg.jpg
mps_no_deg.jpg
overlay.jpg
 
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A simple logarithmic generator.
The 'generator for the generator' is a linear triangle generator, 2.8Vpp & +1.4Vdc offset, to drive the four diode-res segments.
I choose the resistor values to suit various currents through the diodes: 0.01mA, 0.1mA, 1.0mA and 10mA.
A generic instrumentation amplifier (or a regular INA of your choice) with little gain gives 6Vpp output.
As the oscillator cannot display log scales, only the last high (current-) voltage peak is visible.
It's symmetrical due to the original triangle waveform - a sawtooth (not available in tina) would yield an assymmetrical log signal.
 

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