This mono circuit for 10 LEDs was found in the January 1991 Radio Electronics magazine. It is powered by 12 V.
The circuit shown in the figure can either be used to activate a high-power lamp or LED for...
The transistor of this constant current source may be the BC548 or equivalent. Resistor R2 may be...
We found this simple alarm that uses a double contact relay to obtain the lock when triggered. The circuit...