This is a circuit that allows remote activation of a power supply. The circuit was used with a timer of the time. It appeared in the November 1973 issue of Radio Electronics magazine.
This is a combined circuit of tone generator and preamplifier. We found it in a 1975...
We found this simple alarm circuit in a 1986 documentation. The circuit uses sensors of the NA...
We found this circuit in the Linear Applications Handbook by National Semiconductor. The base is...