Tektronix TekRanger 2 TFS3031, Service Manual

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Performance Check – TekRanger 2 (serial nos. B052000 and above)
TFS3031 TekRanger/TekRanger 2 Service Manual
4–25
11. Extrapolate the zero-meter backscatter intercept by drawing a straight line on
the backscatter across the incident pulse to the zero-meter point. See figure
4–10. Note where this line intersects the loss axis, about 29.75 dB in the
example shown below.
Figure 4–10: Singlemode Dynamic-Range Check, Longest Pulse Width, Zero
Intercept
12. Press Zoom Off to turn off zoom. Press SELECT to highlight the cursor
function, then use the arrow keys to move cursor A to145 km (225 for option
10).
13. Press and hold the
Cursor A/Cursor B
softkey to join the two cursors.
14. Move cursor B to 160 km (240 for option 10).
15. Press
Zoom On
. Press
SELECT
to highlight the zoom function, then use
the arrow keys to adjust the zoom so that 30 km of the noise is on the screen.
If necessary, press the
SELECT
button to highlight the trace function, then
use the arrow keys to center the trace on the screen so the tops of the noise
peaks are visible.