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J1A-D11 SPARE
J1A-A12 VIDEO CH3 HI
J1A-B12 VIDEO CH3 LO
J1A-C12 VIDEO CH3 SHIELD
J1A-D12 SPARE
J1A-A13 VIDEO CH2 HI
J1A-B13 VIDEO CH2 LO
J1A-C13 VIDEO CH2 SHIELD
J1A-D13 SPARE
J1A-A14 VIDEO CH1 HI
J1A-B14 VIDEO CH1 LO
J1A-C14 VIDEO CH1 SHIELD
J1A-D14 SPARE
J1A-A15 TEST VIDEO HI
J1A-B15 TEST VIDEO LO
J1A-C15 TEST VIDEO SHIELD
J1A-D15 SPARE
PIN/CONTACT ASSIGNMENTS OF EXTERNAL CONNECTOR J1
Figure 1A (Sheet 2)
Page 4.04
Feb 20/2002
Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
J1 C0NNECTOR MIDDLE PLUG (J1B)
COAX CONTACT FUNCTION
J1B-1 RF VIDEO OUT 1
J1B-2 RF VIDEO OUT 2
J1B-3 RF VIDEO OUT 3
J1B-4 RF VIDEO OUT 4
J1 C0NNECTOR BOTTOM PLUG (J1C)
PIN FUNCTION
J1C-1 SPARE
J1C-2 115 VAC HOT (400 Hz)
J1C-3 CHASSIS GROUND
J1C-4 115 VAC RETURN
J1C-5 SPARE
PIN/CONTACT ASSIGNMENTS OF EXTERNAL CONNECTOR J1
Figure 1A (Sheet 3)
Page 5
Feb 20/2002
Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
3. Functional Description
A. Operation in System
The function of the VMU in a system is as given below. The description
uses System 2000 as an example system.
(1) Figure 2 shows a block diagram of System 2000. System 2000 shown in
Figure 2 is an example only, just necessary to show the position of
the VMU in a system.
(2) The VMU usually supplies RF video signals to an overhead video
distribution network and/or an in-seat video network.
(3) The VMU receives a maximum of 12 video inputs. The four RF video
outputs are applied to:
· A maximum of three columns of tapping units (TU) with a maximum of
12 TUs in each column. The TU demodulates the RF video and
applies the baseband video to a maximum of three overhead monitors
or projectors.
· The in-seat video system through the video system control unit
(VSCU).
(4) The VSCU processes the audio from the video sources for
distribution.
(5) Control of the VSCU done through the cabin management terminal
(CMT). The CMT has the audio/video monitor and control functions.
(6) The in-seat video distribution is doen through the passenger
entertainment system controller (PESC), area distribution boxes
(ADBs) and video audio seat electronic boxes (VASEB). The passenger
makes the video channel selection on his or her passenger control
unit (PCU). The PCU gives the sound and the seat display unit (SDU)
shows the picture at the passenger seat.
Page 6
Feb 20/2002
Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
TU
TU
CRT MONITOR
CRT MONITOR
PROJECTOR
ADB
VASEB
PCU SDU
FDB
VSCU VMU
PESC
CMT VIDEO
AUDIO
DATA AUDIO DATA
RF VIDEO
RF VIDEO
RF VIDEO
RF VIDEO
DATA
TU
TU
FDB
FDB
FDB
ADB
VASEB
PCU SDU
FDB
FDB
FDB
FDB
CDR VCP
BLOCK DIAGRAM OF SYSTEM 2000
Figure 2
Page 7
Feb 20/2002
Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
B. Video Modulator Unit
(1) Figure 3 shows a block diagram of the VMU.
(2) The VMU generates picture carriers and modulates them with the
composite video inputs (NTSC or PAL) for transmission.
(3) The VMU receives a maximum of 12 baseband composite video signals
from video cassette players or equivalent video sources.
(4) The frequency of each picture carrier can be changed through the
VSCU.
(5) The video carrier frequencies are from:
· 139.25 MHz to 295.25 MHz for RD-AA5002-12
· 90.25 MHz to 345.25 MHz for RD-AA5002-22, RD-AA5002-23 and
RD-AA5002-25.
(6) The twelve modulated picture carriers are combined into one RF
video, which is then power-divided into four outputs for
distribution.
(7) The video carrier frequency is set through the internal
microcontroller that receives commands from the VSCU. There
connects an RS-232C serial data link between the VMU and VSCU. The
VSCU uses the RS-232C data link to program and remotely control the
VMU. Channel frequencies and fault status are reported to the VSCU.
(8) If power is applied to the VMU, all modulator channels are
programmed to the frequencies that were set last before removal of
power.
(9) The VMU contains an internal Video Signal Generator (VSG) for BITE
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COMPONENT MAINTENANCE MANUAL Video Modulator Unit (VMU)(17)
