Circuit Description - Sony HDC-900 Maintenance Manual

2. When the turn stops, pull out the remover in the
straight line forcedly.
n
The alignment sleeve can be removed/reinstalled with
the sleeve itself attached to the tip of the remover.
Great care should be taken so as not to lose or damage
the alignment sleeve.
(Alignment sleeve: Sony P/N 9-980-074-01)
Alignment sleeve
3. Clean the tip of the white optical contacts by a cotton
swab moistened with alcohol.
Optical contacts (white)
4. Insert the remover with the alignment sleeve attached
to its tip, and push it until it clicks.
5. Rotate the remover counterclockwise to install the
alignment sleeve, and extract the remover.
Connection connector
After replacing the optical connector of the camera or
HDCU, or replacing the SDI-44/RX-28 board, clean the tip
of the white optical contact of the connection connector by
a cotton swab moistened with alcohol.
HDC-900/950 MM
Optical contact (white)

1-3. Circuit Description

BI-145 board
The BI-145 board supplies the DC bias required for the
CCD. The CCD output is sent through a buffer to the NR-
69 board. The BI-145 board mounts horizontal clock
drivers for the CCD and a reset gate driver.
CN-1947 board
CN-1947 board is the relay board that supplies each CCD
driving pulse generated on the DR-412 board to the BI-145
board. The CN-1947 board also generates the voltage used
for the horizontal clock drivers for the CCD.
DR-412 board
The DR-412 board mounts the vertical clock drivers for
CCD driving, drivers for a shutter pulse and V/H driver.
And the DR-412 board generates the V-sub voltage proper
to the CCD and then supplies it to the CCD.
The voltage produced using a DC/DC converter is sent
through this board to each board.
TG-214 Board
The TG-214 board synchronizes with the CHB-F and
CHB-H signals sent from the SG-268 board to create the
CCD drive pulses and sample-hold pulses. It also PLL
locks the INT-H signal generated in the board with the
CHB-H signal for synchronization.
DPR-154/156 Board
The R, G, and B signals input from the VA-196 board are
A/D converted after passing through the pre-filter.
They are sent the DPR-156 board and returned to the DPR-
154 board again. They are next subject to camera process-
ing such as knee and gamma processing by the DSP IC and
enhancer processing.
The signal output from DSP IC is interfaced with the
DAD-37 board in the digital signal form. It is then D/A
converted and output to the VDA-55 board.
PA-239 board
The CCD output is split into two channels. The PA-239
board is provided with a multiplexer which is used to
return the split signals to thier original state.
NR-69 board
The NR-69 board performs correlative double sampling so
as to extract a reset noise from the CCD output.
1-2. Cleaning of Connector/Cable
1-3. Circuit Description
1-3 (E)