Operating Instructions
1503C MTDR User Manual
1–21
under test to determine whether a waveform represents a physical fault or is simply
an echo from one of the branches. The STORE and VIEW DIFF functions allow you
to see and compare the network with and without branches.
Two important things to be observed when using the VIEW DIFF function:
H
If you change either the VERT SCALE or DIST/DIV, you will no longer be
comparing features that are the same distance apart or of the same magnitude
on the display. It is possible to save a feature (e.g., a connector or tap) at one
distance down the cable and compare it to a similar feature at a different distance
by moving the
n
o
POSITION and
n
o
POSITION controls.
H
When this is done, great care should be taken to make sure the vertical and
horizontal scales are identical for the two waveforms being compared. If either
the stored or current waveform is clipped at the top or bottom of the display, the
difference waveform will be affected.
HORZ SET REF ( mode) allows you to offset the distance reading. For example,
a lead-in cable to a switching network is three feet long and you desire to start the
measurement after the end of the lead-in cable. HORZ SET REF makes it simple.
O
F
F
O
F
F
O
F
F
O
N
ac
0.00 ft
End of
3-ft cable
Figure 1–22: Waveform of Three-Foot Lead-in Cable
1. Turn the NOISE FILTER control to HORZ SET REF. The noise readout on the
LCD will show: set .
2. Turn the
n
o
POSITION control to set the cursor where you want to start the
distance reading. This will be the new zero reference point. For a three-foot
lead-in cable, the cursor should be set at 3.00 ft.
Using Horizontal Set
Reference
Summary of Contents for 1503C
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Page 92: ...Appendix A Specifications A 6 1503C MTDR User Manual...
Page 104: ...Appendis B Operator Performance Checks B 12 1503C MTDR User Manual...
Page 122: ...Glossary Glossary 6 1503C MTDR User Manual...
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