sorry, the note doesn't convince me. A few euros isn't the world, and it's a simpler solution than a transistor.
steven
Steven,
three components (resistor, Z-Diode, Transistor) instead of 5x 10V 5W Zeners is cheaper
and simpler, and fewer components count.
Moreover, any standard power transistor will do and these can be found everywhere, which
is not the case for 5W Zeners or the 25 Watt Zener Larry suggested.
Finally, you can easily heat sink the transistor on the chassis - like the stud mount 25W Zener Larry suggested.
To me this appears to be cheap (bang for the buck), simple (component count), and scalable (power!),
available everywhere and thus
very convincing.
I don't see any reason why you tear this approach down
