Programmable thermostat (CB22136E)

This circuit was found in old English documentation. The sensor is a 1M NTC. The circuit has several trigger levels for key-selected programming.

50 mW Amplifier (CB24449E)
This low-power transistorized amplifier was found in documentation from the 90s. The circuit uses...
Metal Detector (CB12077E)
This circuit is from Popular Electronics from March 1991. It can still be assembled with the...
Symmetric Power Supply (CB15712E)
The voltage of this symmetrical power supply depends on the regulating integrated circuits, which...