User's Manual Part 2

RVP8 User’s Manual
April 2003
TTY Nonvolatile Setups (draft)
3–20
This question permits the state of the triggers during noise measurements to be
consistent and known, regardless of whether the antenna happens to be within a
blanked sector; and you have the additional flexibility of choosing blanked noise
triggers all the time.
Rx–Fixed Triggers: #1:N #2:N #3:N #4:N #5:N #6:N P0:N P1:N Z:N
You have explicit control over which RVP8 trigger outputs are timed relative to the
transmitter pre-fire sequence, versus those which are relative to the actual received
target ranges. Triggers in the first category will be moved left/right by the “L/R”
keys in the Pb plot, and will also be slewed in response to Burst Pulse Tracking.
Triggers in the second category remain fixed relative to “receiver range zero”, and
are not affected by the “L/R” keys or by tracking.
This question specifies which triggers are Tx-relative and which are Rx-relative.
Answer with a sequence of “Y” or “N” responses for each of the six trigger lines, for
the two polarization control lines, and for the timing of the phase control lines. You
should answer No for any trigger that is involved with the pre-fire timing of the
transmitter. If you enable the Burst Pulse Tracker (Section 5.1.3) you will probably
want to assign a Yes to some of your triggers so that they remain fixed relative to the
burst itself.
It is very helpful to have these two categories of trigger start times. Triggers that fire
the transmitter, either directly or indirectly, should all be moved as a group when
hunting for the burst pulse and moving it to the center of the FIR window. However,
triggers that function as range strobes should be fixed relative to range zero, i.e., the
center of that window, and the center of the burst. This distinction becomes
important when the transmitter’s pre-fire delay drifts with time and temperature.
Replace triggers with alternate waveforms: YES
Trigger #1 – 0:Normal, 1–2:Pol0–1, 3–6:PW0–3 : 0
Trigger #2 – 0:Normal, 1–2:Pol0–1, 3–6:PW0–3 : 0
Trigger #3 – 0:Normal, 1–2:Pol0–1, 3–6:PW0–3 : 0
Trigger #4 – 0:Normal, 1–2:Pol0–1, 3–6:PW0–3 : 1
Trigger #5 – 0:Normal, 1–2:Pol0–1, 3–6:PW0–3 : 0
Trigger #6 – 0:Normal, 1–2:Pol0–1, 3–6:PW0–3 : 4
These questions make it possible to reassign the waveforms that are driven onto the
six user trigger (TRIG1–6) BNC outputs on the backpanel of the RVP8. This makes
it easier to adapt the external cabling of the RVP8 so as to make better use of the
available BNC connectors and related 15V drivers. You may substitute either of the
two polarization control lines or the four pulsewidth control lines in place of any of
the six normal triggers.
In the example above, triggers #1, #2, #3, and #5 are all driven with their normal
waveforms. However trigger #4 will have a copy of the POLAR0 polarization
control line, and trigger #6 will have a copy of the PWBW1 pulsewidth control line.
Neither POLAR0 nor PWBW1 themselves are changed by these assignments.
Whenever any of the six user trigger lines is reassigned from its normal setting, the
plot of that trigger within the Pb command will show a hashed line across the screen.
This is a graphical reminder that that trigger has been replaced by some other
waveform.