Noise - Tektronix 1502C User Manual

Noise

1502C MTDR User Manual
On a longer cable, "grass" might appear on the displayed waveform. This is
primarily caused by the cable acting as an antenna, picking up nearby electrical
noise.
1. Set the 1502C front-panel controls:
CABLE
NOISE FILTER
VERT SCALE
DIST/DIV
Vp
POSITION
2. Attach the 50 W terminator to the end of the test cable using the female-to-
female BNC adaptor (both of these items are supplied with the instrument).
3. Increase VERT SCALE to 1.00 mr. Use the
the waveform on the display. As the VERT SCALE setting increases, there
will be noise in the form of a moving, fuzz-like waveform with a few
random spikes.
ac
O
N
O
F
F
O
F
F
O
F
F
Figure 2–14: Noise on the Waveform
4. Turn the NOISE FILTER control clockwise to 8. This will average out much
of the noise.
3-ft cable
1 avg
500 mr
1 ft (0.25 m)
.66
40.000 ft
n
POSITION control to keep
o
40.000 ft
Operator Tutorial
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