This circuit was found in a 90’s 303 Circuits. The components are from the period and the heating system depends on the resistive element.
Found in a Radio Electronics magazine from March 1950, this circuit uses a high-power neon lamp...
This amplifier was found in a 1970s documentation. Darlington transistors can be replaced for modern...
This circuit can generate signals up to 100 kHz. Found in documentation from the 1980s, it makes...