We found this circuit in a Texas Instruments documentation from the 80s. The circuit uses simple power source and the frequency depends on C1 and R1 basically.
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...