This 50 W amplifier was found in the November 1983 Radio Electronics issue. The circuit is suitable for the case and includes a preamp with tone control using off-the-shelf components.
This Nixie pipe circuit was found in 1965 documentation. Note the high supply voltage. Appropriate...
This circuit is from a 1976 publication, but it can be assembled with modern components. For the...
Found in Popular Electronics from the 90's, this circuit consists of an audio oscillator for Morse...