Racal Instruments 3162A/B, User Manual

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User Manual 3162A/B
Using The Instrument 3-38
There is a shift of 1 between the sequence table and the
D-sub connector. With no pins pulled up, the binary value
sensed by the generator is “0”. The sequence table for the
DSUB option ranges from 1 to 256.
Examples:
1. If no pin is pulled up (binary value “0”), the instrument
generates segment 1.
2. If pin 1 is pulled (binary value “1”), the instrument
generates segment 2.
3. Pulling up pins 1 and 3 (binary value “5”) generates
segment 6.
The query:
SEQuence:ADVance:SOURce?
queries the sequence advance source and returns “INT”, “EXT”, “DSUB”,
“TTLT<n>” or “ECLT0”.
Front-Panel / VXIbus
Phase
Synchronization
The Model 3162B can phase lock to a reference signal which is applied to
either the front-panel trigger input or one of the VXIbus backplane trigger lines.
The phase locking process is done automatically by the generator. There is no
need for the user to manually set the generator’s lock-in range for this mode.
A front-panel LED illuminates when the reference signal is valid and the Model
3162B locks onto the reference signal. After lock has been achieved, the
frequency and the start phase of the reference signal and the main output are
identical. The phasing between the two signals may be shifted from 0
E
to
+360
E
.
Note
Minimum phase offset resolution is 8 points. It also
depends on the number of waveform samples. For
instance, if you have minimum 2880 waveform samples,
there is no problem adjusting the phase offset in 1
°°
increments (360
°°
x 8/2880=1
°°
). As another example, if you
have only 1024 waveform samples, the phase offset
increment is 2.81
°°
(2880
°°
/1024 = 2.81
°°
).