Long time intervals with precision (CB9682E)

This precision circuit can provide timings from 0.2 milliseconds to 3 minutes accurately. The circuit is from an 80's documentation.

| Clique na imagem para ampliar |

Shortwave Converter (CB24017E)
This circuit is from a Radio Electronics from March 1970. The crystal depends on the frequency at which...
Magnetic Field Detector (CB25980E)
This circuit detects magnetic fields through a sensor coil, providing a signal in its function. The...
Intercom amplifier (CB23690E)
Described in an article that taught how to assemble the complete intercom in Radio Electronics magazine...