This sensitive circuit was found in an Electronics Hobbyists Handbook from the 1990s. The circuit can use common general-purpose transistors in place of the original ones.
This sensitive two-transistor circuit was found in the June 1965 Radio Electronics magazine. The...
This two-digit digital pressure gauge was found in the 1992 special edition of Radio Electronics...
This circuit is from a 1976 technical documentation. In it we have the way of tuning a circuit using...