Found in an Electronic Design of 1964, this circuit operates with control voltages from 0 to 12 V determining the duration of the pulses.
The circuit below is suggested by National Semiconductor in its 1994 Linear Applications Handbook. The...
This 9 + 9 V symmetrical power supply was obtained in a 1977 symmetric publication but can still be...
This circuit was obtained from a Popular Electronics of the 1990s. The circuit uses a temperature...