hello
the IRPD sensor when tested without controller makes the status led on if enable pin is given 5v even in the absence of obstacle. applied electrical tape around the ir led and on three sides of detector still the problem exists.
when tried to observe the output at different point of the circuit. at the 8th pin of ic 74HC00 i.e., nand gate output of the oscillator part is only 18khz and not 38khz.
and as soon as enable pin is applied 5v the detector goes low and hence the status led becomes on.
plz suggest me what i should do to make my sensor work as desired.