Hi all !
As you noticed well Michael, T2 plays an important role in the feedback loop.
Can you try to figure out what it does ?
In the meanwhile, here is the same circuit but made with the legacy parts.
Don’t forget that this circuit uses a positive GND, so mount C1 and the battery accordingly !
R2 is changed into 4,7K to make it work.
Do you think that we can swap T1 & T2 ?
Remeber that the legacy transistors have a build in resistor which influence the bias of the transistors !