We found this circuit in a Philips documentation from 1965. The circuit uses a common LDR sensor and the transistors are general purpose types. TR2 can be a BD135.
This circuit for measuring very low currents was found in an American documentation from the...
The charging current of this circuit is controlled by the temperature of the accumulators, which is...
This circuit was obtained from old documentation and has a very simple 6 or 12 V configuration...