Mini drill control (CB8767E)

This control for 12 V drills was found in a 90s Elektor. The components are current, and Q1 can be replaced by a TIP42 mounted on a heat radiator.

| Clique na imagem para ampliar |

Controlling a blinking LED with LDR (CB24662E)
The figure shows how to control the blinking of a 5 V blinking LED with an LDR. The LED only...
Band pass amplifier (CB7447E)
Suggested by Maxim in documentation from the 90s, this circuit has its response curve given next to...
Temperature Alarm (CB6111E)
This circuit is from a 1965 General Electric publication. It uses a thermistor to fire a reed...