We found this circuit in the Audio Handbook of the National Semiconductor of 1977. The circuit is used to recover vinyl media for recording on other media.
When the input of this circuit goes to high level, the LEDs start to flash alternately. The...
This circuit already uses an integrated circuit from the time. Note the different encapsulation of the...
This power charger was found in a 1990s issue of Popular Electronics. Integrated circuits must be...