Agilent Technologies 1153A, Руководство пользователя и обслуживания

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Service
Probe troubleshooting
Probe troubleshooting
Use the following procedures to assist in troubleshooting problems with the 1153A
Differential Probe.
Preparing the probe for troubleshooting
The probe bottom cover must be removed before troubleshooting to allow access to
signals where the probe cable connects to the pc board.
1
Remove the probe tip caps and probe tips.
2
Loosen the probe clamp ring at the cable end of the probe (1/4 turn counter-
clockwise) and slide it down the cable.
3
Remove the bottom cover.
a
At the cable end of the probe, separate the covers about one centimeter (1/2 inch).
b
Slide the bottom (curved) cover toward the cable end of the probe until the locator
pins at the probe end of the bottom cover clear the holes. Remove the cover.
Troubleshooting the probe
1
Connect the probe to the channel input of an Infinuum oscilloscope. This will
supply power to the probe amplifier and correctly terminate the probe output.
2
Apply a known signal from a signal source to the coaxial connector on the test
board using a coaxial cable.
3
Connect the probe to the test board in the position shown in the figure below
(signal to + input) and note the displayed output on the oscilloscope.
Figure 3-1
Signal to + input
4
Check for an identical output at the solder connection where the probe cable
attaches to the probe pc board.
If the probe output cable is unterminated, or the coax is open, the output signal will be
about twice the amplitude of the input signal.