Bilateral current source 2 (CB20819E)

We found this circuit in an American publication from the 1980s. Equivalent modern operational amplifiers can be used.

Automatic Garage Lamp (CB16634E)
We found this circuit in a 1987 documentation. Its purpose is to turn on a garage light using the...
Oscillator with frequency triplicator (CB4052E)
The oscillator of this circuit operates around 8 MHz, but the output will be at a frequency three times...
Cascading the 4520 (CB083E)
For counting to values higher than 16, many 4520 can be cascaded as shown in Figure . The EN...