This circuit is from March 1978 Radio Electronics. The 4-digit circuit uses a period module and is battery powered. The main integrated circuits are CMOS and TLL.
This circuit is from the National Semiconductor Audio Handbook. The amplifier operates with 6 V...
This switched filter was found in the 1969 documentation. The FET should be current-matched and eventually...
This independently charged circuit was found in a 1969 EEE. The operational amplifier supports a...