Elenco Motion Detector Kit - Manual (Page 14)

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TROUBLESHOOTING GUIDE
The values given below are approximate.
POWER SUPPLY
1. Measure the voltage at IC3. Pin 3 = 9V, Pin 1 = 4.75 - 5.25V
A. Check soldering around IC3 and C6.
B. Check for short to GND from pins 2 and 3.
C. If no shorts are present, IC3 may be defective.
INFRARED DETECTOR
2. Measure the voltages at points: A = 5V
B = 4.25V
C = .700V
A. Voltage at point A incorrect:
1. Check R1.
2. Check for a short between point A and GND.
B. Voltage at point B incorrect:
1. Check R1, C1 for correct value.
2. Check for a short between point B and GND.
C. Voltage at point C incorrect:
1. Check R2, C2 for correct value.
2. Check for a short between point B and GND.
C B A
OPERATIONAL AMPLIFIERS
3. Measure the voltages at IC1 while the unit is at standby.
Pin Voltage Pin Voltage
1 3.80V 8 –
2 – 9 1.62V
3 1.40V 10 1.60V
4 5.00V 11 –
5 1.40V 12 1.52V
6 1.60V 13 1.55V
7 – 14 1.50 - 1.60V