This circuit uses the LM2931 which is not a common component today. What it does is to activate a lamp causing it to blink at a frequency determined by the capacitor.
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This circuit with signal acceptance filter was found in the June 1993 Electronics Now magazine. Other...
We found this 555 integrated-circuit tester in an old Electronics Hobbyst from 1977. The circuit is...
Found in a1969’s neon lamp documentation, this circuit uses a high voltage transistor. The output...