Operator Tutorial
1502C MTDR User Manual 2–3
O
N
ac 0.000 ft
O
F
F
Figure 2–1: Display Showing 3-ft Cable in Start-Up Conditions
3. The rising pulse on the left is the test pulse (incident pulse) leaving the
instrument. The rising reflected pulse on the right displays the echo coming
back. Turn the
n
o
POSITION control clockwise until the cursor rests on the
rising edge of the reflected pulse.
O
F
F
O
F
F
O
F
F
O
N
ac 3.000 ft
Incident
Pulse
Reflected
Pulse
Figure 2–2: Cursor of Rising Edge of Reflected Pulse
The upper right corner should read 3.000 ft. Note that the reflected pulse
rises. This is the classic signature of an open cable, a point of higher
impedance.
4. Adjust the VERT SCALE control. This will increase the height of the pulse.
For accurate measurements, the pulse should occupy most of the display.
Note that the LCD shows the VERT SCALE setting in mr. For now, set this
control to 354 mr/div.