This FM micro transmitter was found in an 80s spy book. The circuit can work with equivalent FETs and is powered by a voltage of 0.6 to 6 V. Details of the coil are given next to the diagram.
This circuit is from a technical publication on voltage regulators from 1977. The transistor can...
This analog frequency meter for low frequencies was found in Radio Electronics magazine from July...
This circuit is from the 1983 Intersil Databook. The circuit operates on a 9 V battery and has a...