TM 11-6625-3081-23
7-31. VIDEO SIGNAL GENERATOR (VSG) CASE ASSEMBLY 2A2A7A1
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INPUT CODE: VSGST
a .
DESCRIPTION
This module tests the ability of video signal generator (VSG) case assembly
2A2A7A1 to produce video output signals in response to input function commands.
If an error is detected during any of the following checks, a prompt is
displayed at the completion of the test.
The VSG is programmed for a 525 line rate and the blanking level to 0.3 volts.
The displayed video output is measured by the programmable digitizer assembly, which
is triggered by the VSG and the following checks made:
The horizontal sync width for 4.0 to 6.0 microseconds.
The horizontal sync period for 60.0 to 68.0 microseconds.
The porch level of display output signal for -0.075 to +0.75 vdc.
The difference between the porch level and sync level for 0.1 to 0.4 vdc.
The time from the start of the last horizontal sync of the even field to the
beginning of the odd vertical field for 60.0 to 68.0 microseconds.
The time from the start of the odd field vertical sync to the start of the
first pulse for 25.0 to 30.0 microseconds.
The time from the start of the odd field vertical sync to the start of the
sixth pulse for 188.0 to 196.0 microseconds.
The time of the start of the sixth pulse of the odd field vertical sync to
the next positive transition for 6.0 to 14.0 microseconds.
The time from the first positive transition after the odd field vertical sync
to the start of the next horizontal sync for 55.0 to 63.0 microseconds.
The time from the start of the last horizontal sync of the odd field to the
beginning of the even field vertical sync for 25.0 to 35.0 microseconds.
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