TM 11-6625-3081-23
7-30. PROGRAMMABLE PULSE GENERATOR (PPG)
7-30
INPUT CODE: PPGTST
a. DESCRIPTION
This module tests the ability of the programmable pulse generator (PPG)
2A2A7A6A8 to produce correct output pulses in response to input function commands.
Each of the four output channels is programmed for a test pulse which is checked
using the programmable digitizer assembly 2A2A1.
PPG output 1 is programmed for a 1.0 microsecond positive pulse. The PPG gating
feature is programmed to switch off every other pulse resulting in a period of 10
microseconds.
The measured pulse is checked for a pulse width of 0.95 to 1.05
microseconds with a period of 9.95 to 10.05 microseconds, a low state of -0.5 to
+0.8 vdc, and a high state of +2.5 to +5.5 vdc.
An error in the pulse measurements will display a prompt at the completion of
the test.
PPG output 2 is programmed for a 2.0 microsecond positive pulse. The PPG gating
feature is programmed to switch off every other pulse resulting in a period of 10
microseconds.
The measured pulse is checked for a pulse width of 1.95 to 2.05
microseconds with a period of 9.95 to 10.05 microseconds, a low state of -0.5 to
+0.8 vdc, and a high state of +2.5 to +5.5 vdc.
An error in the pulse measurements will display a prompt at the completion of
the test.
PPG output 3 is programmed for a 3.0 microsecond positive pulse. The PPG gating
feature is programmed to switch off every other pulse resulting in a period of 10
microseconds.
The measured pulse is checked for a pulse width of 2.95 to 3.05
microseconds with a period of 9.95 to 10.05 microseconds, a low state of -0.5 to
+0.8 vdc, and a high state of +2.5 to +5.5 vdc.
An error in the pulse measurements will display a prompt at the completion of
the test.
PPG output 4 is programmed for a 4.0 microsecond positive pulse. The PPG gating
feature is programmed to switch off every other pulse resulting in a period of 10
microseconds.
The measured pulse is checked for a pulse width of 3.95 to 4.05
microseconds with a period of 9.95 to 10.05 microseconds, a low state of -0.5 to
+0.8 vdc, and a high state of +2.5 to +5.5 vdc.
An error in the pulse measurements will display a prompt at the completion of
the test.
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