Hi Frank,

    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!


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