Cursed circuits #6: reverse avalanche oscillator

You can even use it to make a simple audio synth: https://www.lookmumnocomputer.com/simplest-oscillator

This isn't particularly cursed. I mean we've had avalanche pulse generators for well over half a century easily. It's just exploiting semiconductor characteristics they don't teach you in the usual garbage undergrad textbooks.

https://en.wikipedia.org/wiki/Pearson%E2%80%93Anson_effect

I would never have thought to try this circuit for fear of letting out the transistor's magic smoke.

What would happen if you added a capacitor (to ground) on the base? Could you adjust the frequency?

Delightfully cursed.

I wonder how consistent the breakdown voltages are between manufacturers? I mean, I am sure there is some spec, but is it not just a minimum in this case?