This sophisticated moving bar indicator circuit with the LM3915 is from a Radio Electronics magazine from May 1985. The two-channel circuit includes the power supply.
This commercial amplifier uses germanium transistors from the era. It was found in a Japanese...
This circuit from a Radio Electronics magazine from June 1969 already shows the use of the newly...
This TTL circuit was found in a 1978 technical documentation. The power must be supplied with 5 V....