Dear friends,

I have made a light dimmer (controlled by 2051). In place of variable resistor (required to manually control the dimming), I have used a combination of LDR and LED (per standard applicaiton notes I found).

But the response of the LDR is slow. If you move from full bright to full dim, it takes about 3 to 4 seconds for it to take effect, i.e. with the dimming of LED (which is instantaneous), the resistance of LDR increases very slowly and the light dims as slowly.

I intend to replace the turtle (LDR) with a leopard (phototransistor). So I intend to use 4N35 optocoupler.

My question is, shall it dim the light by varying the voltage accross 4N35's LED ???

Babar/