Bench thermometer (CB20501E)

With an ultra-low consumption, this circuit can be powered by solar cells. The circuit is from a 1991 documentation.

UAA170 LED Drive (CB21891E)
This UAA170 application circuit was taken from Siemens' own integrated circuits manual from 1976....
Low Frequency Astable (CB470E)
The astable multivibrator shown by the figure can produce signals in the 10 to 10 000 Hz band...
20 W per channel NEC amplifier (CB6984E)
Found in an American publication from the 1980s, this circuit can be found in commercial sound...