TM 11-6625-3081-23
1-24. TEST CONSOLE TEST BENCH 2A2 (cont)
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h. ELECTRONICS DRAWER ASSEMBLY 2A2A7
(1) General.
Electronics drawer assembly 2A2A7 (FO-25) contains many elec-
tronic components used for a variety of E/O bench functions. Nine CCAs are used for
motor control, temperature measurements, pulse generation, and signal multiplexing.
A camera head control unit receives video images, changes these images to electrical
signals, and transmits these signals to a FIFO memory for temporary storage. A
video signal generator receives pulses of information from the programmable pulse
generator (PPG) and converts these pulses to video information and clock signals.
Power for the video signal generator is supplied by the heat sink assembly. A relay
assembly supplies control signals to the E/O bench.
(2) Video Signal Generator (VSG) 2A2A7A1.
The VSG receives signals (CAMERA
VIDEO, R0-R7) from PPG #1 (2A2A7A6A8), signals (WINDOW, BH BLANK, B VID SYNC,
6.25MHZ) from PPG #2 (2A2A7A6A9), and a CLOCK signal (200MHZ) from programmable
digitizer 2A2A1.
Video signals are generated in the VSG by analog CCA A1 and the
clock is generated by digital CCA A2.
These signals are routed to VHF cable entry
panel 2A2A2 for use during test.
(3) Camera Head Control Unit 2A2A7A3.
(a) Camera head control unit 2A2A7A3 is matched to the internal camera
head, located in the dayside test bench.
The camera uses the General Electric
charge induced device (CID) which is essentially an array of photo detectors whose
outputs are converted to digital format as the camera scans at a TV rate.
(b) Camera head (CID video camera) output is transmitted to its matched
camera head control unit.
The output of the camera head control unit is transmitted
to FIFO memory 2A2A7A6A5.
(4) Relay Assembly 2A2A7A4.
Refer to FO-26 for illustration of relay assembly
2A2A7A4.
Digital output signals from multiprogrammer assembly 2A2A6 are routed to
relays K1 through K12.
Relays K13 through K15 are not used. All 15 relays are
energized by a signal (+5V SS RELAYS) from FIFO memory CCA 2A2A7A6A5.
(5) Heat Sink Assembly 2A2A7A5.
The heat sink assembly consists of a power
transistor and a resistor mounted on a heat sink.
It provides the voltage needed
the video signal generator 2A2A7A1.
(6) Motor Control.
The motor drive CCA (2A2A7A6A1), motor
(2A2A7A6A2), and motor mux CCA (2A2A7A6A3) control nine motors in
in the dayside test bench, one in the nightside test bench, and
console test bench.
by
logic CCA
the EO bench; five
three in the test
Change 20
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