simple garage stop light circuit


Posted on Feb 5, 2014

A novel use of solar cells makes positioning your car in the garage rather easier than old tyres, a mirror, or a chalk mark. The six solar cells in figure 1 serve as power supply and as proximity sensor. They are commercially available at relative low cost. The voltage developed across potentiometer Pi is mainly dependent on the intensity of the l


simple garage stop light circuit
Click here to download the full size of the above Circuit.

ight falling onto the cells. The circuit is only actuated when the main beam of one of the car`s headlights shines direct onto the cells from a distance of about 200 mm (8 inches). The distance can be varied somewhat with P, Under those conditions, the voltage developed across C1 is about 3 V, which is sufficient to trigger relaxation oscillator Ni. The BC547B is then switched on via buffer N2 so that D3 begins to lfash. Diodes Di and D2 provide an additional in- crease in the threshold of the circuit. The total voltage drop of 1. 2 V across them ensures that the potential at pin I of the 4093 is always 1. 2 V below the voltage developed by the solar cells. As the trip level of Ni lies at about 50 per cent of the supply voltage, the oscillator will only start when the supply voltage is higher than 2. 4 V. The circuit, including the solar cells, is best constructed on a small veroboard as shown in figure 3, and then fitted in a translucent or transparent man- made fibre case. The case is fitted onto the garage wall in a position where one of the car`s headlights shines direct onto it. The LED is fitted onto the same wall, but a little higher so that it is in easy view of the driver of the car. When you drive into the garage, you must, of course, remember to switch on the main beam of your headlights!




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Digital To Analog Converter Circuit
    Solid State Power Controllers
    NiMH battery charger circuit diagram using LTC4060
    Projects
    About Area 50
    Audio Signal Generator
    One light emitting diode display circuit
    Clapp oscillator
    Voice music outlet circuit diagram SK- made
    Machine magnechuck under current protection circuit diagram



    Top