Frequency Doubler MC1595L (CB14589E)

We found this circuit in Motorola's Linear Databook in 1990. The component used is not common today.

Sensitive Metal Detector (CB4406E)
This circuit was found in a 1992 documentation and has excellent sensitivity, using components that...
Switching amplifier (CB9001E)
We found this circuit in an old American documentation. The circuit applies to modern equivalent...
Water Level Indicator (CB6268E)
This circuit was found in an English publication from the 80's. It triggers a buzzer (with...