Found in a 1966 Electronics World, this circuit applies to the protection of any analog instrument. The diodes can be of any general-purpose type.
We found this chopper circuit in a 1967 publication. The transistors are of the time, and current...
This circuit was found in a 1977 Radio Handbook. The ports used are CMOS like 4001 and the...
Ohmite TGHD non Inductive High Power Resistors Available in SOT-227 enclosures, these Ohmite...