This circuit is intended for underwater communications. Of course, the critical point is the shielding to avoid water. The circuit is from an Electronic Hobbysts Handbook from the 90s.
This circuit only detects variations in light falling on the sensor. The circuit uses an LM380 as a...
This latched switch configuration was obtained from National Semiconductor documentation on the...
This electronic roulette circuit with 10 numbers was found in a Popular Electronics from the 80s....