Audio Frequency Meter (CB20477E)

Found in a Popular Electronics from 1992, this circuit uses a PLL567 in an audio meter bridge that has zero indication via LEDs.

1,2 to 1,4 V Power Supply (MSB004E)
Common diodes when forward biased present a voltage fall of about 0.6 to 0.7 V. This voltage fall...
MIC28515 5A Switching Regulator
August 2017 - Mouser Electronics has already for dispatch Microchip MIC28515 Controlled Regulators for...
555 Two-Tone Siren (NI010E)
Two alternating are produced by this circuit. The output signal must be applied to a power stage...