hi J,Hi,
thanks for showing me that circuit!
I tried it and it's true, it is working I get 4mA to 20mA.
The transistor and the op-amp are not heating! But it's R11 that is heating now. I used a 1/4W.
Correct me if Im wrong but. In R11 there's 24V with a maximum of 20mA. So 20mA*24V = 0,48mW
If I take a resistor of 1W I should be ok?
If the dissipation is 0.48W , use a 1W