This circuit was obtained from an American documentation from 1968. The current depends on the operational, observing that the circuit uses a symmetrical power supply.
This circuit was found in Philips documentation from 1967. The phototransistor is from that time,...
This source gently applies the voltage to the load, causing it to rise slowly, thus avoiding...
We found this adapter in a 1970s American documentation on instrumentation. It is suitable for analog...