This circuit was found in a Popular Electronics from the 90s. The circuit has temperature compensation. Coil and capacitors depend on the frequency at which the circuit will be used.
This high-gain amplifier was found in the March 1994 issue of Electronics Now magazine. The...
This is a small transistor receiver for the medium wave range made in Japan in the 1960s. The...
This water or moisture sensor circuit was found in the February 1984 Radio Electronics magazine. The...