TM 11-6625-3081-23
1-24.
TEST CONSOLE TEST BENCH 2A2 (cont)
1-24
d.
OPTICAL SIGNAL GENERATOR (OSG) 2A2A3
(1) General.
OSG 2A2A3 (FO-21) provides optical stimuli to test and evaluate
EO multiplexer TV sensor UUTs.
Imaging port is used for the TV sensor and
collimating port is for the EO multiplexer.
Both imaging and collimating ports share
a common light source.
Their optical information is modified by an assortment of
filters, target data, and optical elements as needed.
Uniformity port is used by both
TV sensor and EO multiplexer.
This port provides diffused light by using a sphere and
independent light source.
(2) Imaging Port Operation.
This port is used to mount TV sensor UUT and
provides target information for testing.
(a) Relay bracket assembly 2A2A3A1 has 28-volt relay power applied to one
side of relay coils K1 and K2.
Positive lamp power is also applied to A contacts of
K1 and K2.
When proper signals are received and decoded by amplifier-detector
assembly 2A2A3A4, COLLIMATOR/IMAGE LAMP ENABLE signal (ground) is sent to relay
bracket assembly and energizes relay K1, closing contacts A and B.
(b) A halogen lamp (2A2A3DS1) is located beneath lamp shield assembly
2A2A3A2.
Negative lamp power (ground) is applied to one side of lamp 2A2A3DS1. When
relay 2A2A3A1K1 is energized, positive lamp power is routed through A contacts to
light lamp 2A2A3DS1.
(c) A light sensor is located on light shield assembly 2A2A3A2. This sensor
is biased on when lamp 2A2A3DS1 is lit, sending signal COLLIMATOR/IMAGE LAMP DETECT to
relay bracket assembly 2A2A3A1.
This signal passes through closed B contacts of relay
K1 and routed to amplifier-detector assembly 2A2A3A4.
This signal is then fed to a
comparator.
The comparator outputs an analog signal (OSG DETECTOR) to analog-to-
digital converter assembly 2A2A13 where it is converted for use by the computer to
control lamp intensity.
(d) Optical routing of light is first through the optical filter assembly
and lens target assembly.
Optical filter diffuses the light and lens target assembly
provides a target image required for the TV sensor UUT.
This image is then relayed by
two 90-degree fixed fold mirrors to optical relay assembly. The optical relay
assembly contains eight lens elements and an aperture providing a target image
reduction ratio of 2:1.
The final image is routed through the imaging port and to the
TV sensor UUT.
(3) Collimating Port Operation.
This port is used to mount the EO multiplex;
and provides target information for testing.
(a) Lamp and sensor operation are identical to the imaging port. Refer to
paragraph (2)(a) through (2)(c) above.
(b) Optical routing is through the collimator assembly and out the
collimating port.
Collimator assembly contains a filter, condenser, target, and lens
doublets and collimators.
Light enters in and passes through a filter, condenser, and
target.
Target assembly provides an optical image pattern for EO multiplexer. This
image is modified by a collimator element, two doublet elements, another collimator
element and doublet before exiting the collimator assembly.
This final image is
passed through the collimating port and to the EO multiplexer UUT.
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