6-3
BVM-D9H1U/D9H5U/D9H1E/D9H5E/D9H1A/D9H5A
10. B1 Board
The B1 board is an aperture correction circuit.
The aperture correction performs the frequency compensa-
tion at 5 MHz when the input signal is 480/60i and 575/
501 with DL400/DL401. It performs the frequency
compensation at 16 MHz with DL402 and DL403 when
any other signals are input.
DL404 and DL405 are the delay lines that correct the delay
amount of the Y-signal. The PB and PR signals are
corrected of their delay by DL501, DL502, DL503 and
DL504.
Amount of compensation can be varied by 2 to 6 dB when
the APT is ON using the IC450 aperture correction
amplifier.
11. Sync Separator Circuit/B2 Board
The sync separator circuit consists of the sync AGC circuit
and the B2 board.
Either the input sync signal in the modes of 480/60i and
575/50i or that in any other modes, is selected by IC3301
(2/3), (3/3), Q3302 and Q3303. The sync signal is separat-
ed by the SYNC AGC circuit of Q3304 to Q3319.
Either INT sync or EXT sync is selected by IC3301 (1/3).
In the B2 board, the equalizing pulses are extracted by
IC3901, the H. sync pulse is separated by the H. SYNC
SEP circuit consisting of IC3904, IC3905, IC3906 and
IC3907. The V. sync pulse is separated by the V. SYNC
SEP. circuit consisting of Q3905, Q3907, Q3908.
The switch IC3902 is the selector switch that selects either
the internal sync separator output or the already separated
H. and V. sync signals that are input when the SDI signal
is used.
12. Drive circuit
IC2345 is the R-signal drive circuit.
Q2377 is the auto cut-off circuit. Output pulse form
Q2377 flows through R3363 through Q2346 when Q2377
is turned ON.
The reference pulse that is current-to-voltage converted by
R3363 is input to IC1401 pin-25 through a buffer in the B
board in order to activate the auto cut-off circuit.
The same circuit operation is applied to the G-signal circuit
and the B-signal circuit.
6-3. MA board
1. System Control
IC106 (system control CPU) controls the monitor in
accordance with the program that is installed in IC108
(flash EEPROM). The program in IC108 can be re-written
by the boot loader program in IC106. Various settings are
saved in the SRAM (IC111) that is backed up by battery.
2. Internal Bus inside Monitor
Most blocks of the deflection circuit and the signal circuit
are controlled by the I2C bus that is driven by IC103 (5/6),
(6/6). The I2C bus is controlled of its operation by
controlling the general purpose port of IC106 by software.
IC112 is an expansion I/O unit that is used to control the
internal bus and the TALLY LED.
3. Connection to Options
The respective option boards are controlled by IC101 (1/4),
(2/4), (3/4), IC103 (1/6), (2/6), (3/6), (4/6) and IC104. The
data communication between the monitor and the option
slot bus uses the strobe/hand-shake method using the
SLOT ID signal. Data is transferred by MISO/MOSI/
SCLK. The MISO/MOSI/SCLK signal is also used for
communication between the MA board and the MB board.
IC112 is the RS-422 driver that establishes communication
to read the key data or knob information of the internal
controller or of the control unit and to turn on/off the
LEDs.
6-4. MB board
1. Character Display and Internal Signal
Generator
IC1107 is the character generator IC such as menu charac-
ters. IC1110 generates the 4:3 marker and the various
signals for automatic adjustments.
Outputs of the two ICs are mixed by IC1100 and are
output.
2. Serial Communication Driver
IC1105 is the communication controller for the serial
remote control. It performs the transmission and reception
of the serial remote communication data together with the
RS-485 driver of IC1103 and IC1106.
IC1108 (communication controller) and IC1109 (RS-232
driver) perform the transmission and reception of the
OPTION terminals.
3. Parallel Remote Control
IC1112 reads out the status of the parallel remote terminal
and transfers it to the CPU in the MA board.
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