This circuit for the 60 kHz range was found in 73 magazine and published in 1995. The circuit uses a ferrite rod. Note the direction of the coil windings.
This unijunction transistor oscillator is intended for Morse code practice. The circuit is from an...
Despite being from an old documentation, this circuit is currently feasible just by using modern...
This circuit was found in a 1966 EEE. It is intended for automatic switching of the measurement range of...