Metal locator (CB7506E)

This simple metal detector was found in a 1960 Sylvania transistor manual. The phone must be high impedance or crystal.

LED Flasher 7400 (CB13719E)
This traditional TTL configuration was obtained in a 1977 documentation. The supply must be made...
Ignition for cars with positive ground (CB23628E)
Another electronic ignition circuit for cars with positive ground. This circuit is from a Radio...
Touch Switch or Water Alarm 4001 (CB16319E)
The presence of a low resistance between the terminals of the sensor causes this modulated...