This circuit is from American documentation from the 1980s. FETs support modern equivalents.
We find this circuit in a 1970 publication. Transistors can be replaced by current equivalents and LDR is...
Featuring low output impedance and high input impedance, this configuration was found in a 1980s...
Found in a 1980s American documentation, this circuit can use a SCR and a general-purpose transistor....
