This circuit is from a Radio Electronics from April 1964. The circuit uses power transistors of the time, which must be mounted on a good heat radiator. Modern equivalents can be used.
Found in Popular Electronics from the 1980s, this circuit can use more modern transistors such as...
This circuit is from a Radio Electronics from February 1970. The integrated circuit is an...
This is stage is transformer coupled and was found in na old publication of the year 1958. The...