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
4–47
10. 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
4–26. Note where this line intersects the loss axis, 21 dB in the example
shown below.
Figure 4–26: Multimode Dynamic-Range Check Zero Intercept, Longest Pulse Width
11. Press
Zoom Off
to turn off zoom. Press
SELECT
to highlight the cursor
function, then use the arrow keys to move cursor A to 16 km for 1300 nm, or
to 9.5 km for 850 nm.
12. Press and hold the Cursor A/Cursor B softkey to join the two cursors.
13. Move cursor B to 16.1 km for 1300 nm, or to 9.6 for 850 nm.
14. Press Zoom On . Press SELECT to highlight the zoom function, then use
the arrow keys to adjust the zoom so that 200 m of the noise is on the screen
for 1300 nm, and 100 m of noise is visible for 850 nm. Select the trace
function and use the arrow keys to move the trace if necessary, in order to
see the tops of the noise spikes.