This 130 V drive uses an integrated circuit not very easy to find, which is the LM143. The circuit is suggested by National Semiconductor in its 1994 Linear Applications Handbook.
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...