Microchip Technology GPS-2700, Руководство пользователя

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GPS-2700 User’s Guide
DS50003016A-page 74
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2020 Microchip Technology Inc.
You may select a size of the exported images in X and Y. The file format may be
.bmp
,
.jpg
,
.gif
, or
.png
. Your settings will be stored and will be the default next time you
open this dialog.
If you choose to export the graph, you might want to override the TI max setting in force
on the screen display. You may do this by entering a non-zero value into the “Override
TI” control. A value of zero causes the export to take the same setting if any as the
screen display.
The export may be done automatically on a timed basis. Simply enter a non-zero value
in seconds to choose an export time interval. To manually export in accordance with
the settings, press the “Export” button.
FIGURE 5-8: Captured Data Example.
FIGURE 5-9: Zoomed Captured Data Example.
5.4 INTERPRETING THE DATA
Figure 5-8 shows the data acquired by the GPS-2700 unit over a period of more than
200 hours. The red trace is EFC (CSAC frequency steering value). The crystal is aging
(becoming faster in frequency over time). This requires the steering value to be
increased to maintain precisely 10.0
MHz. A drift of 67 parts-per-trillion (1E-12) is