Vaisala RVP900, User Manual

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Figure 24 Test Pattern Display
1. In the TTY monitor type: P+
This prints the message
Plotting Test Pattern...
on the TTY and then produces the
plot shown in the following figure. The display is an overlay of the following strokes:
• Bottom line
• Middle line
• Top line
• Line sloping up
• Line sloping down
• Sine wave pattern that changes phase with each plot so that it appears to radiate
from the left side of the display.
2. When you are satisfied that the plot is drawn correctly, type Q or press ESC to return to
the TTY monitor.
6.5
Pb
— Plot Burst Pulse Timing
For magnetron radars, RVP900 relies on samples of the transmit pulse to lock the phase of
its synthesized
I and Q data and to run the AFC feedback loop.
Use the
Pb
command to adjust the trigger timing and A/D sampling window so that the
burst pulse is correctly measured.
6.5.1 Interpreting the Burst Timing Plot
The following figure shows an example of a burst timing display plot of a successful capture
of the transmitter's burst pulse.
RVP900 User Guide M211322EN-J
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