This circuit was found in a 1980s documentation. Similar configurations appear in the section, but from different sources. The circuit makes use of components of the time.
This is an old test circuit for integrated TTL counters, feeding a Nixie tube, common at the time....
This traditional crystal radio circuit, but which has a modern version with diode, was found in an...
This headphone amplifier using a pickup coil can be used as an extension for devices such as TVs,...