This circuit is from Motorola's Linear Databook from 1990. The integrated circuit and transistors are uncommon, but the circuit can be assembled with equivalents.
This circuit uses the flip-flops from the previous circuit to implement a 3-digit binary counter. The...
The voltage comparator used in this application is the NCX2220 from NXP. What this circuit does is...
The UVTRON tube is an ultraviolet radiation sensor. In this circuit from Radio Electronics from...