This circuit was found in the May 1959 Radio Electronics magazine. Its purpose is to provide bias voltages for circuits under test. The circuit is isolated from the power grid.
This circuit produces the sound of percussion such as blocks, drum, bell, etc. The frequency...
We found this oscillator in a publication from the 1960s. The frequency is around 600 Hz with the...
Found in a Popular Electronics from 1992, this circuit uses a PLL567 in an audio meter bridge that...