Battery charger (CB9121E)

Found in an Electronics Now from the 1980s, this circuit uses some components that are still common today. For others, equivalents can be tested.

| Clique na imagem para ampliar |

Polarity Test (CB14701E)
This polarity test or indicator indicates the polarity of a power line by LEDs. The circuit is...
Digital clock MM53149 (CB24361E)
This is the circuit of a digital clock published in the January 1975 issue of Radio Electronics magazine....
Powergrid timer (CB9364E)
Found in an Elektor from the 90s, this circuit can be powered directly by the power grid. The...