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PCS500 Troubleshooting
If there are any fails or problems when you run the PCS500_TST.EXE at the first time on a new oscilloscope unit please make the following checks:
Test 1
Problem No power
Check The voltage at pin 6 of optocoupler IC30 should go down at the startup for a moment. See images 1 and 2. Check IC4, IC21, IC30 and the associated components.
2, 3
No trace on the screen
Check all the supply voltages of the digital and analog section. Check the voltages of the input amplifier section. See image A. Check the waveforms at the optocouplers. See images 2 ... 8. When measuring the waveforms use "Single" mode and keep triggering ON.
4 5 6 7 8 9 10 11 12 13 14 15 16
Calibration error Can't be adjusted Can't be adjusted Can't be adjusted Can't be adjusted Can't be adjusted Can't be adjusted Calibration error Can't be adjusted Can't be adjusted Test failed Test failed Power can't be switched off
Open CALIBRATION.LOG file and check the failed test. Below there are more detailed comments (Table1). Check the input section components (C14, C15, C80) Check the input section components (C14, C15, C80) Check the input section components (C20, C21, C81) Check the input section components (C20, C21, C81) Check the resistors of the input attenuator and the amplifier section. Check the resistors of the input attenuator and the amplifier section. Open CALIBRATION.LOG file and check the failed test. Below there are more detailed comments (Table1). Check the resistors of the input attenuator and the amplifier section. Check the voltages at IC24 (See image B). Check transistor T5 and associated components. Check the divider circuits IC9, IC10, IC11 and associated components. Check the trigger section components. The voltage at pin 6 of optocoupler IC30 should look like the waveform of image 2. Check IC4, IC21, IC30 and the associated components.
Calibration results Test CH1 offset at 15V/div CH2 offset at 15V/div CH1 correction at 5V/div CH2 correction at 5V/div CH1 correction at 15mV/div CH2 correction at 15mV/div CH1 correction at 5mV/div CH2 correction at 5mV/div CH1 correction at 20us/div CH2 correction at 20us/div CH1 correction at 10us/div CH2 correction at 10us/div CH1 correction at 5us/div CH2 correction at 5us/div CH1 Trigger low CH1 Trigger middle CH1 Trigger high CH2 Trigger low CH2 Trigger middle CH2 Trigger high EXT Trigger middle Typical result 119 125 2 3 2 3 6 8 1 1 -1 -2 -5 -7 98 124 150 102 126 152 84 Table 1. OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK Acceptance range 100...156 100...156 -50...50 -50...50 -50...50 -50...50 -50...50 -50...50 -50...50 -50...50 -50...50 -50...50 -50...50 -50...50 50...200 (CH1 Trigger low)+15...200 (CH1 Trigger middle)+15...200 50...200 (CH2 Trigger low)+15...200 (CH2 Trigger middle)+15...200 50...200
Voltages of the analog input section and the trigger section. All the voltage values below are allusive approximations only.
A
B C
0.0V 1.6V D 0.0V
-3.4V
Y-position Up Middle Down
Voltage A 0.0V 2.3V 4.8V
Voltage B -3.3V -2.6V -1.7V
Voltage C 1.1V 1.8V 2.6V
Voltage D 1.7V 2.5V 3.3V
Image A. Voltages of the input section.
0.6V
0.0V
-4.4V
E
1.9V 1.9V
1GS/s mode Test 13 2.4 ... 2.6V
Image B. Voltages of the trigger section.
Waveform images. All waveforms are captured using PCS500 in Single shot mode. Note: Look only the pulse amplitude and the pulse lengths. The pulse sequence (waveform) may be different.
Image 1. The voltage at pin 6 of optocoupler IC30 when Power ON Test (1) is selected.
Image 2. The voltage at pin 6 of optocoupler IC30 when Power OFF Test (16) is selected.
Image 3. The voltage at pin 6 of optocoupler IC20 when Test 2 is selected.
Image 4. The voltage at pin 6 of optocoupler IC29 when Test 2 is selected.
Image 5. The voltage at pin 6 of optocoupler IC30 when Test 2 is selected.
Image 6. The voltage at pin 6 of optocoupler IC31 when Test 2 is selected.
Image 7. The voltage at pin 3 of optocoupler IC41 when Test 2 is selected.
Image 8. The voltage at pin 3 of optocoupler IC42 when Test 2 is selected.
Image 9. The voltage at pin 3 of optocoupler IC43 when Test 2 is selected.
Table 1 Typical calibration results in the CALIBRATION.LOG file. Test CH1 offset at 15V/div : CH2 offset at 15V/div : CH1 correction at 5V/div : CH2 correction at 5V/div : CH1 correction at 15mV/div : CH2 correction at 15mV/div : CH1 correction at 5mV/div : CH2 correction at 5mV/div : CH1 correction at 20us/div : CH2 correction at 20us/div : CH1 correction at 10us/div : CH2 correction at 10us/div : CH1 correction at 5us/div : CH2 correction at 5us/div : CH1 Trigger low : CH1 Trigger middle : CH1 Trigger high : CH2 Trigger low : CH2 Trigger middle : CH2 Trigger high : EXT Trigger middle : Typical result 119 125 2 3 2 3 6 8 1 1 -1 -2 -5 -7 98 124 150 102 126 152 84 Possible reason if there is "FAIL" instead of "OK" Faulty relay, faulty IC19 Faulty relay, faulty IC21 Wrong offset adjustment RV3 or faulty relay Wrong offset adjustment RV4 or faulty relay Wrong offset adjustment RV3 or faulty relay Wrong offset adjustment RV4 or faulty relay Wrong offset adjustment RV3 or faulty relay Wrong offset adjustment RV4 or faulty relay
OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK OK
Check the trigger section components Check the trigger section components Check the trigger section components Check the trigger section components Check the trigger section components Check the trigger section components Check the trigger section components