Found in Mallory documentation from 1968 this circuit uses an integrated circuit from that time. The circuit has a flat response from 10 Hz to 700 kHz.
This configuration was found in a 1976 documentation. Note the use of pin 4 input for reset. The...
This circuit, found in documentation from the 1990s, uses a common 7-segment LED display. The...
This circuit is suggested by National Semiconductor in its Linear Applications Handbook. It makes...