This simple TTL siren was found in a 1980s Electronics Today International. The power supply is 5 V and the integrated circuit can be the 7400.
This audio-driven relay was published in the July 1977 issue of Radio Electronics magazine. The...
This circuit can be used for signaling a panel with a common incandescent lamp. The lamp will...
This crystal oscillator is indicated for the calibration of IF steps of common radio receivers. The...