GE Corometrics 126, Руководство по обслуживанию

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Revision B 120 Series Maternal/Fetal Monitor 7-17
2015590-001
Calibration: Display Check
Checking a 3.5” x 4.5” Display
Newer monitors contain a 3.5” x 4.5” display. In troubleshooting, the following
methods can be employed to determine whether a problem exists with the display
assembly, the 120 Series Monitor DSP Board or the interconnect cable.
Verifying the DSP Board Operation
1. Turn off the 120 Series Monitor.
2. Remove the nine screws which secure the monitor top cover. Four screws are
located on the bottom of the monitor and five screws are located in the back.
3. Remove the cover by sliding it toward the rear of the monitor.
4. Unplug the display interconnect cable from J5 on the DSP Board.
5. Turn on the 120 Series Monitor.
6. Using a digital voltmeter, attach the negative lead to J5 (pin 20), ground, on the
DSP Board. Attach the positive lead to J5 (pin 1). Verify a reading of +12 Vdc
± 1.2 Vdc. This checks for the presence of the Vcc2 signal.
7. Attach the positive lead to J5 (pin 5) on the DSP Board. Leave the negative
lead attached to ground. Verify a reading of +5 Vdc ± 0.25 Vdc. This checks
for the presence of the Vcc1 signal.
8. Using an oscilloscope, attach the negative lead to J5 (pin 20), ground, on the
DSP Board. Attach the positive lead to J5 (pin 9). Verify the output of a
periodic waveform. This checks for the presence of the HSYNCB signal.
9. Attach the positive lead to J5 (pin 7) on the DSP Board. Leave the negative
lead attached to ground. Verify the output of a periodic waveform. This checks
for the presence of the VSYNCB signal.
10. Attach the positive lead to J5 (pin 11). Leave the negative lead attached to
ground. Verify the output of a period waveform. This checks for the presence
of the VCKB signal.
11. If you suspect that the DSP Board is not supplying the correct voltage or one of
the video signals is missing and you have another properly functioning 120
Series Monitor, substitute the DSP Board and check for proper operation.
Contact your GE Service Representative for information about repair/exchange
of the DSP Board.
12. If you suspect that the interconnect cable is not working properly, refer to
“Chapter 14, Replacement Parts” or contact your GE Service Representative for
part ordering information.