USER’S MANUAL__________________________________________________________________
148 _________________________________________________________________ M211322EN-D
5.3.3 TTY Information Lines Within Pb
The TTY information lines resemble:
Zoom:x2, PlotSpan:5 usec, FIR:1.36 usec (49 Taps)
IF:Ch5(TXB)
Freq:27.817 MHz, Pwr:–53.9 dBm, DC:0.14%,
Trig#1:–5.00, BPT:0.00
Z/z The Z command zooms the amplitude of the burst pulse
samples so that they can be seen more easily. The value is
reported on the TTY as "Zoom".
> and < The live plotted data can be logged to the
$(IRIS_LOG)/rvp9–pb.log text file; one line per plot.
% Toggle between all five IFDR IF-Input sources.
B/b These keys temporarily disable or re-enable the Burst Pulse
Tracker. The tracker must be disabled in order for the L/R
keys to be used to shift the nominal trigger timing. The "b"
key disables tracking and sets the trigger slew to zero; the
"B" key re-enables tracking starting from that zero value.
+ The + subcommand initiates a hunt for the burst pulse.
Progress messages are printed as successive AFC values
are tried, and the trigger slew and AFC level are set
according to where the pulse was found. If no burst pulse
are found, then the previous trigger slew and AFC are not
changed.
Zoom Indicates the magnification (in amplitude) of the plotted
samples. A zoom level of "x1" means that a full scale A/D
waveform exactly fills the height of the sample window.
Generally, the signal strength of the burst pulse is not quite
this high. Thus, use larger zoom levels to see the weaker
samples more clearly. You may zoom in powers of two up
to x128.
PlotSpan Indicates the overall time span in microseconds of the
complete scope display, from left edge to right edge.
FIR Indicates the length of the impulse response of the matched
FIR filter, and hence, the duration of the burst pulse sample
window. The length is reported both as a number of taps,
and as a time duration in microseconds.
Freq Indicates the mean frequency of the burst, derived from a
fourth order correlation model. The control parameters for
this model are set using the Mb command (Section 4.2.6
Mb — Burst Pulse and AFC on page 126).
To Next Page
Loading...
Need help?
General