A simple workshop generator m.cz.

Mateusz_konstruktor .... that's a question for me ????, what bulbs are we talking about.
I would like to add that I currently have two more RC PG-23 generators that came to me for repair and the customers have not reported so far.
In the service, the above-mentioned generators in a soap dish housing with a 4.5 volt flat battery worked reliably due to their handyness and simplicity.
73!

@dipole
What bulb did your colleague use, in terms of rated voltage or a specific type?

Bulb usually 12 V with a current of 5-20 mA.

@Mateusz_konstruktor, for example, from manual telephone exchanges. 24V/20mA.