Alarm Buzzer (CB24392E)

This circuit was found in July 1975 Radio Electronics magazine. Power depends on the trigger transistor and the effects of capacitors C1 and C2.

| Clique na imagem para ampliar |

Ultra High Gain FET Stage (CB14146E)
The circuit shown has a voltage gain of 500 times and can use equivalent FETs like the BF245. The...
Light comparator (CB7368E)
Found in a 1968 Novel Electronics Circuit, this circuit compares two light intensities using...
Proximity Relay (CB12835E)
We found this circuit in an old publication from Argentina. The relay must be of the sensitive type,...