This simple circuit for a common 110 V power grid was found in a 1980s American documentation. The circuit uses neon lamps as indicators.
This amplifier was found in the November 1973 issue of Radio Electronics magazine. The power...
This circuit is for transducers (headphones or speakers) of 200 to 300 ohms. The frequency is...
This regenerative detector circuit operates over a wide range of frequencies. The circuit was...