problem in IR sensor circuit
![[IMG]](proxy.php?image=http%3A%2F%2Fimg28.imageshack.us%2Fimg28%2F7703%2F73790520.jpg&hash=8b5593a48751fd56965ffd66acca9c77)
i made this circuit on breadboard and when powered it with 9V battery the red LED started glowing. then i placed a piece of white cardboard with a 2cm thick black line over the IR LED and detector but the red LED doesnt stops glowing neither on black surface nor on white surface.😒😕
this is the spacing of my IR LED and IR detector as on breadboard-
![[IMG]](proxy.php?image=http%3A%2F%2Fimg180.imageshack.us%2Fimg180%2F7258%2F011020092744.jpg&hash=091740fb24c0dd47e58522f3d9c02e44)
i could not understand what the problem is.😒😒😒 please help.😕😕😕