We found this circuit in a 1967 General Electric SCR manual. The time is set to R1 and depends on C1 which must be a low-leak capacitor.
This low drift or offset circuit is from an 80's documentation. The configuration can be made with...
This is a commercial circuit from a Japanese publication from 1972. The circuit uses a FET that...
This instrumentation amplifier was obtained from Popular Electronics in 1993. The operational...