ARMY TM 5-6675-238-14
MARINE CORPS TM 08839A-14/1
Table 3-1. PADS Test Set Controls, Indicators, and Connectors
NOTE
This table covers only items used by the opera-
tor; items used by higher level maintenance
personnel are covered in instructions for the
appropriate maintenance level.
Control, indicator, or connector
Function
Signal processor unit (figure 3-1)
+28 VDC fuse indicator
Lights when fuse in + 28V power supply AC line has
blown
BLOWER fuse indicator
Lights when fuse in blower inverter power line has blown
+ 5 VDC fuse indicator
Lights when fuse in + 5V power supply AC line has blown
-15 VDC fuse indicator
Lights when fuse in -15V power supply AC line has blown
+15 VDC fuse indicator
Lights when fuse in + 15V power supply AC line has
blown
SPU ON switch-indicator
Controls application of primary AC power to the SPU and
lights when power is applied
FAILURE/ACTION indicator
Indicates the cause of a failure or operator action required
during SPU self-test
LAMP TEST switch
Causes all front panel indicators to light when pressed and
a sequence of numbers to be displayed on FAILURE/
ACTION indicator. Does not function when SELF TEST
switch-indicator is activated
SELF TEST switch-indicator
Used to activate SPU self-test. Lights when activated. Does
not function when in lamp test
PARITY ERROR/VERIFY ERROR
PARITY ERROR lights if a parity error occurs while the
indicator
SPU is reading tape or while being addressed by the
computer serial data bus. A tape error will cause the
tape reader to stop on the faulty character
REVERSE switch-indicator
MEMORY LOAD switch-indicator
VERIFY switch-indicator
IMU FAIL/COMP FAIL indicator
VERIFY ERROR lights if data loaded into computer mem-
ory did not verify correctly when checked against the
tape data from which it was loaded. Such an error will
cause the tape reader to stop on the character group
which did not verify correctly
Used to reverse direction of tape on tape reader. Lights
when activated
Causes tape reader control circuitry in SPU to be initialized
and issues run command to tape reader, Lights when
activated
Causes the computer to compare the data that was loaded
into memory with the data being reread from the tape.
The tape will stop on a character group that is not
properly verified. Lights when activated
Indicates a failure in the IMU and/or computer
3-5
