Low temperature sensor (CB7814E)

Found in 90s Radio Electronics, this circuit is indicated for reading temperatures below zero.

TTL interface for CMOS (CB7036E)
Suggested by Harris in documentation from the 80s, this circuit uses components from that time. It...
75 V with 10 mA Voltage Regulator (CB820E)
This high-voltage regulator uses only two components. The resistor is a wound wire type with 1 W...
Impact meter (CB7343E)
This circuit uses an impact sensor transistor called Pitran rare today. The circuit is from 1969...