This 3-valve receiver was found in a publication by Edelman from 1924. The circuit has two supply voltages, B being 60 to 90 V.
This circuit was obtained in a 1991 Electronics Handbook. The publication no longer exists, but...
We found this circuit in Ferranti's 1974 transistor manual. The components are from the period. Note...
This instrumentation amplifier was obtained from Popular Electronics in 1993. The operational...