Lie Detector (T1534E)

This circuit was found in a Popular Electronics from December 1956. Power is provided by batteries.

Thermally Controlled Nicad Charger (CB15549E)
The charging current of this circuit is controlled by the temperature of the accumulators, which is...
Mini organ with Vibrato (CB16427E)
We found this circuit in a 1987 magazine, but the use of still common components allows its...
Symmetrical 9 V Power Supply (CB18699E)
This circuit was originally designed to power the CB18698's MSX interface, but it is suitable for...