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 |

Alarm with NO and NC Sensors (CB4806E)
Radio Electronics magazine published in a 90's issue this simple alarm that can use any general...
Programming the Duty Cycle (CIR101E)
The previous oscillators that use gatesshown in this section, and the 4093 in the basic version,...
Signal Tracer (CB921E)
This circuit consists of a good perfromance audio amplifier powered from two or four batteries and has...