GE Corometrics 250cx Series, Service Manual, Page: 130 / 252

4-50 250cx Series Maternal/Fetal Monitor Revision C
2036947-001
Maintenance: Calibration
Calibration
This section of the manual provides a calibration procedure which allows authorized
service personnel to perform an instrument alignment using a minimum of test
equipment. This procedure is not intended to replace a complete instrument
checkout and alignment as performed at the GE factory. It should be considered a
performance check and troubleshooting guide to be used in conjunction with other
information supplied throughout this service manual. It is important to mention, this
section of the manual is not intended as a substitute for proper professional training,
or familiarity with the monitor. Only qualified service personnel should attempt
servicing the 250cx Series Monitor.
Before You Begin Electronic Calibration
General
Refer to the assembly drawings for the location of adjustments and test points
referred to in this section. The board assembly drawing numbers are given for each
board in this section. The electronic calibration procedure outlined in this section
necessitates removal of the monitor’s top cover. Also, the following equipment will
be needed in order to carry out the procedural steps.
„ Digital Voltmeter, 4 1/2 digit or equivalent
„
Plastic Alignment Tool
„ Oscilloscope
Handling Precautions
The following guidelines should be followed when handling circuit boards
or assemblies containing circuit boards . Following these procedures helps
resist damage that can be caused by static electricity.
„
Discharge any static charge you may have built up before handling parts.
„ Wear a grounded, anti-static wristband at all times.
„
Use a static-free work surface.
„ Store items in anti-static bags or boxes.
„
Do not remove items from anti-static containers until needed.
Power Supply Voltages—Verification
There are no adjustments for the power supply voltages; however, you can verify
them as follows:
Main Board Power Supply Voltages
Using a digital voltmeter, measure and verify the power supply voltages using the
J14
connector on the Main Board. Refer to Table 13.
NOTE:
There are no adjustments for these voltages.