the circuit is very useful and effective – so I built a special block to meet my needs. The light bulb can bee changed to have different limits, from 2…20 Ω resistance (cold) of the filament, depending of the actual experiment(s). This is – by the way – the answer of your question above 🙂
Here I use a 5.3V 0.3A light bulb to have a limitation at about 125mA (the light bulb to the right is a 0.1A type!):
Thanks again, Frank!
- This reply was modified 3 years, 7 months ago by Michael. Reason: Changed font and size styling for easier reading