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We found this circuit in a PE Hobbyst Handbook from the 90s. The components are common, except the Geiger tube. The transformer is also a component that requires care when choosing.
Found in Popular Electronics this circuit will trigger a buzzer if the ignition key is removed...
Found in Popular Electronics, this sophisticated short-wave receiver requires a lot of skill from...
This circuit is from an old American documentation using LEDs in the rectification. The circuit...