This is the simplest Regenerative (Regen) Reflexive (Reflex) radio ever.
The simplest two transistor radio that is capable of driving a speaker.
You may know about the one transistor capable of driving a speaker but the difference here is the voltage. The one transistor radio needed high voltage to function and transformer to have 180 degree phase shift.
No diode used to detect the audio.
Also, no capacitor is used to control the regen but a 1k variable resistor.
On the other hand the LC circuit is easy to be changed to receive other bands like the short wave.