TEST CONSOLE TEST BENCH 22 (cont)
(4) Uniformity Port Operation.
The uniformity port is used to perform shading
tests for both EO multiplexer and TV sensor UUTs.
Its purpose is to provide an even
diffused light source with no hot spots.
(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 the A contacts
of K1 and K2.
When proper signals are received and decoded by amplifier-detector
assembly 2A2A3A4, UNIFORMITY LAMP POWER signal (ground) is sent to relay bracket
assembly and energizes relay K2 closing contacts A and B.
(b) Three halogen lamps (2A2A3A5DS1 - DS3) are located within integration
sphere assembly 2A2A3A5.
Negative lamp power (ground) is applied to one side of lamps
2A2A3A5DS1 - DS3.
When relay 2A2A3A1K2 is energized, positive lamp is routed through
the A contacts to light lamps 2A2A3A5DS1 - DS3.
(c) Integrator light sensor 2A2A3A3 is located above and in front of
integration sphere 2A2A3A5.
This sensor is biased on when lamps 2A2A3A5DS1 - DS3 are
lit, sending signal UNIFORMITY LAMP DETECT to relay bracket assembly 2A2A3A1. This
signal passes through the closed B contacts of relay K2 and routed to amplifier-
detector assembly 2A2A3A4.
This signal is fed to a comparator. The comparator
outputs an analog signal (OSG DETECTOR) to analog-to-digital converter assembly
It is converted for use by the computer to control lamp intensity.
(d) The optical path is controlled by the integration sphere. The sphere
houses three halogen lamps which are uniformly spaced. When lit, light from these
lamps are reflected around and about the inside of the sphere. The inside of the
sphere is coated with barium sulfide.
This material diffuses light and evenly
distributes light to provide a uniform light source.
Light exits the sphere through
the uniformity port and is inputed to a TV sensor or EO multiplexer UUT.
e . TEST ADAPTER PANEL ASSEMBLY 2A2A4
The test adapter panel assembly 2A2A4 (FO-22) contains four con-
nectors, a relay assembly, and a terminal block.
(a) Augmentation programmable interface connection (APIC) connector J1
connects 120 output lines from the matrix switch assembly 2A2A1O to the major test
(b) Dedicated interface unit (DIU) connector J6 connects lines from the
matrix switch assembly 2A2A1O, electronics drawer assembly 242A7, and relay assembly
2A2A4A1 to external equipment.