TM 1-6625-476-30
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2-6. TEST DESCRIPTION. (CONT)
a. AUTOMATICALLY EXECUTE ALL TESTS IN ORDER. You should normally select this option to
begin testing a TADS NSA UUT. Also select it if you are not sure which specific test you want to run. At
the AVIM level, the program will run tests 2 through 8. At the depot level, it will run tests 2 through 10. If
other menu selections have already been successfully performed, only those that have not passed or
have not been selected will be performed. If the TADS NSA passes all tests, an ALL TESTS GO prompt
will appear on the VDT.
b. ELECTRONICS TEST. This test checks DC supply voltages and periodic waveforms as well as
various command and sense voltages that are developed by the UUT. During the test you may be
prompted to adjust a potentiometer if a regulated voltage is out of tolerance.
c. OPTICS TEST. This test checks optical field-of-view switching and athermalization functions of the
UUT and examines the displayed video for narcissus. During the test you may be prompted to adjust up
to six potentiometers if an out-of-tolerance condition exists. Some UUT configurations will also provide
testing for optical filter selection, built-in-test operation, and various optical mode command functions.
d. BORESIGHT TEST. This test checks the boresight of the FUR in all three FOV, and visual
multiplexer boresight in the zoom (underscan) mode. If boresight is out of tolerance, you will be directed
by the program to adjust the visual collimator lens on top of the scanner assembly. During each
boresight test, you will be asked if a white triangle is present on the video monitor, in order to verify that
the visual multiplexer vidicon beam current has not drifted out of specification during operational use. If
the triangle is not white, you will be directed to replace the visual multiplexer. A dead channel check will
also be performed. External boresight used in the TADS auto boresight camera function is also checked.
If an out-of-tolerance condition exists, you will be directed by the program to perform channel balance.
e. ZOOM TEST. This test checks the electronic magnification function of the visual multiplexer. During
this test, the narrow FOV system intensity transfer (SIT) target on the video monitor will increase to twice
the size, then return to its original size.
f.
AUTOMATIC CONTROL MODULE (ACM) TEST. This test checks the ACM to ensure that the FUR
can automatically adjust itself to the brightness and contrast of the target and the area around the target.
No adjustments are associated with the ACM test.
g. MODULATION TRANSFER FUNCTION (MTF) TEST. This test checks the focus of the three FOV in
the system. If an out-of-tolerance condition exists, you will be directed to adjust a potentiometer on the
focus adjustment pot CCA. It is assumed that if any FOV passes, the visual multiplexer and IR imager
are not defective. If all three FOVs fail, or if two FOVs fail after adjustment, you will be directed to adjust
the video multiplexer focus ring. If at any time the athermalization test fails for the medium FOV, you will
be directed to adjust the IR imager focus ring and to readjust potentiometers on the focus adjustment pot
CCA. If, after adjustment, any MTF parameter is still out of tolerance, you will be given the opportunity to
repeat any of the adjustments you believe may improve the focus of the system.
h. NOISE EQUIV. TEMP. DIFF. (NETD)/MIN. RES. TEMP. (MRT) TEST. This test checks the video
noise value, expressed in temperature difference units, of the thermal imaging and detection circuitry
used to generate a clear resolvable video output. There are no operator adjustments.
