Remote control tester (CB7823E)

This circuit from a 90s Electronics Now, uses a 4010 gate as a signal amplifier. The circuit triggers an indicator LED.

Voltage to Current Converter for LEDs (CB21623E)
This common transistor-based circuit provides power for 20 mA common white LEDs from a single 1.5...
Broadband Amplifier (CB21860E)
This circuit has a voltage gain of 30 times and passband of 14 MHz. The circuit is from the 1974...
Instrumentation Amplifier (CB12173E)
This instrumentation amplifier was obtained from Popular Electronics in 1993. The operational...