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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Found in a PE Hobbyst in 1991, this 13.6 V power supply with a 2 A current is suitable for supply...
This signal injector and tracer (follower) was found in an old American documentation. The...
The Variable Frequency Oscillator (VFO) shown in the figure can generate signals in a frequency...