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 amplifier can be used for public-address or other applications. Three transistors of the time...
This circuit was found in a 1967 Electronics World. The circuit uses components of the time that...
This circuit was obtained in a June 1987 magazine Hands-On. It is a circuit that indicates on an...