I am attempting to duplicate the comparator portion of the circuit shown here under question 17: http://www.allaboutcircuits.com/worksheets/opamp2.html .
The schematic of my breadboard is attached. I have double checked my wiring and believe it to be correct, however the circuit does not operate as expected. I can see the voltage at the LDR junction change as vary the amount of light varies on each LDR, but I have not been able to light either LED. I have tried varying both pots at both extremes, and currently have them set at mid range. I know the op-amp is good, the power is properly connected, the LED's are good. What could be wrong?
Thanks.
ETA: Never mind. It was a pot in wrong. I have corrected the attached schematic to show the pots in the correct orientation. Rotating the pots clockwise will produce maximum sensitivity.
The schematic of my breadboard is attached. I have double checked my wiring and believe it to be correct, however the circuit does not operate as expected. I can see the voltage at the LDR junction change as vary the amount of light varies on each LDR, but I have not been able to light either LED. I have tried varying both pots at both extremes, and currently have them set at mid range. I know the op-amp is good, the power is properly connected, the LED's are good. What could be wrong?
Thanks.
ETA: Never mind. It was a pot in wrong. I have corrected the attached schematic to show the pots in the correct orientation. Rotating the pots clockwise will produce maximum sensitivity.
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