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 high-gain circuit uses junction FETs (JFETs) and must be powered by somewhat high voltages. The...
This circuit counts 1 per second, displaying the value in binary. The circuit is TTL and must be...
Critical components of this project are the Geiger tube and the 300V battery. The battery can be...