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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We find this circuit in the 80's own component manual itself. The characteristics of the circuit...
We found this amplifier with high input impedance and low capacitance, using FET, in a...
This circuit was obtained in a 1979 magazine, but it can be easily assembled today, as the...