I found tis circuit in na old documentation from 1958. The circuit uses germanium transistor availble that time and hard to obtain today. The circuit is indicated for phono applications using variable reluctance transducer.
This old circuit (1968) uses a germanium transistor to drive a relazy from a switch. The circuit...
The basic integrated circuits of this 1988 multimeter are no longer very common today, but if...
This 50 kHz to 250 W circuit was found in an old RCA documentation. The transformer is a...