B. Operator Performance Checks
3. Connect one end of the 36 in. reference cable to a capable pulse measurement device and the
other end of the 36 in. reference cable to the CT100B front panel cable connector. A trace
should appear on the device display.
4. Switch the CT100B into the Short pulse setting from the Main menu Cable Len setting.
5. Measure the pulse frequency coming off the front panel cable connector. The averaged pulse
frequency should be 250.0±0.2 kHz for Short, 50.00±0.04 kHz for Medium, and 12.50±0.02
kHz for Long.
6. Repeat pulse frequency check for Medium and Long settings.
B.4.7 Sequential Sampling Rate Check
The sequential sampling rate is the reciprocal of the pulse repetition time.
B.4.8 Vertical Scale Check
Twist the VERTICAL SCALE knob clockwise. Vertical scale should drop to 0.5 millirho/div and
the trace should expand accordingly.
B.4.9 Vertical Accuracy Check (millirho)
1. Attach an open to the CT100B.
2. Position a cursor on the trace so that it is well after the open.
3. The vertical measurement should be between 940 millirho and 1060 millirho.
B.4.10 Vertical Position Check
1. Increase vertical scale to 500 mρ/div by turning the VERTICAL SCALE knob
counterclockwise.
2. Use the VERTICAL POSITION knob to move the live trace completely above the horizontal
midline of the screen.
3. Use the VERTICAL POSITION knob to move the live trace completely below the horizontal
midline of the screen.
A CT100B must succeed at both operations to pass the Vertical Position Check.
B.4.11 Distance Cursor Resolution Check
Distance cursor resolution is a value determined by a constant. It can be measured by counting
distinct locations that a cursor may occupy between two division lines, including one of the
division lines.
118 CT100B TDR Cable Analyzers Operator’s Manual
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