Programmable Countdown Timer (CB25198E)

We found this circuit in the February 1989 issue of Radio Electronics magazine. The selectors are BCD programming switches. The circuit is CMOS.

| Clique na imagem para ampliar |

Delayed Alarm Trigger (CB4775E)
This circuit is designed to activate an automotive alarm after 8 minutes of activation. Of course...
Reinartz Oscillator (CB25318E)
The coils determine the frequency of this oscillator that we found in the January 1996 issue of...
Simple Timer Using the 555 (MSB123E)
This simple timer can be used in many applications such as egg timer. The LED glows up when S1 is...