We found this circuit in the March 1984 issue of Radio Electronics magazine. The module used is a common type at the time. The other integrated circuits are common types.
Found in a 1964 General Electric documentation, this circuit uses PUTs that are not currently...
This double tone generator uses a specific integrated circuit, having been found in a 1977 CMOS...
Found in American documentation from 1968, this circuit has an acute cut-off of the frequency to...