PH meter (CB20731E)

This circuit was obtained in an old American documentation. The integrated circuit used is uncommon today. Modern equivalents can be searched.

| Clique na imagem para ampliar |

AC Line Interference Filter (CB452)
This filters blocks radio interference or noise coming from the AC Power line. Noise such as the...
Shutdown circuit 2 (CB8419E)
Found in a 90s Popular Electronics, this circuit triggers a relay in case of overvoltage. Can be used as a...
Alarm System (CB16793E)
We found this sophisticated home alarm in a 1994 documentation. The circuit supports sensors of...