Monostable 4047 (CB25123E)

This re-triggerable circuit was found in the April 1988 Radio Electronics magazine. Timings are given by R1 and C1.

Analog frequency meter (CB6906E)
This circuit is from a 1969 Electronics World. The transistors may be modern general-purpose...
Infrared people detector (CB7022E)
This circuit was obtained from Radio Electronics from the 90s. The infrared sensor is of an...
Home Security System (CB4868E)
This control panel allows the use of NO and NC sensors, turning the alarm on after 30 seconds...