Found in 1969 documentation, this circuit supplies a load after an interval given by R1 and C1. These components can be changed to other times.
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...