Solar charger MC34064 (CB14537E)

The integrated circuit used in this charger is not very common today. The circuit is from Motorola's 1990 Linear Databook.

Humidity Monitor (CB24940E)
Using a period sensor, this circuit was found in the February 1986 issue of Radio Electronics...
Multipurpose Alarm (CB17301E)
We found this simple alarm circuit in a 1986 documentation. The circuit uses sensors of the NA...
Modulated light receiver (CB19581E)
This circuit is from an American documentation from the 70's using transistors of general use of...