TM 11-6625-3081-23
2-14. MODULE DESCRIPTIONS (cont)
2-14
c. TEST CONSOLE TEST BENCH 2A2 (cont)
Input Code
DIGITST (cont)
DIGALIGN
Description
Channel B is programmed to 1 V/D, POS +4, and coupling to
ground.
The data is sampled, moved to a matrix, and averaged.
The averaged sampled data is checked for 240 to 255. A 5V p-p,
10 kHz sine wave is applied to channel A input B. The sample
rate is programmed to 0.1 microseconds per sample.
The period
of the sampled signal is checked for 99.0 to 101.0 microseconds.
The signal measured by the programmable digitizer assembly is
checked for 4.75 to 5.25v p-p.
A 5V p-p, 10 kHz sine wave is
applied to channel B, input B.
The sample rate is programmed to
0.1 microseconds per sample.
The period of the sampled signal
is checked for 99.0 to 101.0 microseconds.
The signal measured
by the programmable digitizer assembly is checked for 4.75 to
5.25v p-p.
This module provides programmable digitizer 2A2A1 positioning
alinement, gain alinement, and a check of the trigger level.
Positioning alinement is performed with the inputs grounded.
Minimum requirements for the positioning of each channel are:
Position: -4
>0.0 and <21.0 counts
Position: -3
32 +/- 21 counts
Position: O
128 +/- 21 counts
Position: 3
223 +/- 21 counts
Position: 4
>234 and <255 counts
The actual values are displayed.
The operator is then prompted
to remove the appropriate preamplifier with power removed, and
to adjust the POSN GAIN and POSN CTR controls on the
preamplifier.
The new positioning alinement values are then
checked.
This process continues until the operator ends the
adjustment process.
For the gain alinement, the gain voltages are checked at 0.2,
0.5, and 1.0 volts/division.
If the voltages are not within
2 percent of the applied voltage, the operator is prompted to
adjust the front panel GAIN control. Adjustments within
5 percent of the desired voltage level will pass, but
adjustments within 2 percent are desired.
For the trigger level check, the actual trigger level values are
displayed along with the programmed levels. No adjustments are
provided.
Change 9
2-77
