Sony KP 48S70, Руководство по обучению

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The following features are new to the RA-4A chassis and are not found on
the RA-4 chassis:
“1080I Capable”
ƒ
Enables you to display 1080I, 480P and 480I digital TV formats. The
set does not accept 720P format. 480I signals are upgraded to 960I
by DRC.
ƒ
The 480P signal can be displayed two different ways by changing the
Aspect Ratio in the Set Up menu: V Compressed, 16:9; or normal,
4:3.
ƒ
These signals can be input to the Video 5 input only. Component or
RGB with sync inputs are accepted using phono jacks. Not compat-
ible with computers 5 BNC connectors.
ƒ
The Video 5 input cannot use the MID circuit; therefore, PIP and P&P
functions cannot use Video 5.
Parental Control
Enables or disables the V chip rating system to block programs that might
be inappropriate for younger viewers.
RA-4 and RA-4A Circuit Differences
The following differences will be discussed in this manual:
ƒ
Video Path – The new video path will be discussed using an overall
video block, a DTV Video Processing block and DTV Video Process-
ing section which shows the IC and pin numbers that the DTV video
path uses.
ƒ
Addition of V chip circuitry. The Main CPU controls the main picture V
Chip. There is a separate Sub video V Chip. This will be covered in
the video block section.
ƒ
VD Mute circuit – Due to the fact that this set displays a true 16:9
picture in a cabinet with a 4:3 aspect ratio, the IK reference pulses
that are output during every field need to be hidden. If correction was
not made, these lines would be visible at the top of a 16:9 picture.
This circuit takes the IK reference pulses and CC data and puts them
in the normal 4:3 overscan area by placing a pulse into the vertical
drive signal.
The following are minor circuit differences that will not be covered in this
manual:
ƒ
The component values in the H deflection circuit have been changed
because displaying 1080I input requires a different scan rate. The
two different scan rates are 31.5 kHz for DRC, MID, 480I and 480P,
and 33 kHz, which is used for 1080I video.
ƒ
There are now three separate banks of NVM for three separate regis-
tration modes. These modes are 1080I, 960I (Normal DRC picture)
and 480P 16:9 Aspect Ratio. The set automatically selects the regis-
ter bank of whichever signal is input. This is not covered because the
adjustments remain the same for each mode.
ƒ
The pincushion correction circuit has been changed for greater effi-
ciency. It is similar to the HV Regulation Control circuit used in the
RA-4 chassis.
ƒ
New Picture tubes are used but are functionally the same.
ƒ
The 3D Comb Filter is identical but now resides on the BA board alone.
The BA board plugs into the A board.
ƒ
The Shading circuit is different due to CRT burn countermeasures
installed because of the use of the 16:9 aspect ratio on a unit with a
4:3 screen. These countermeasures are proprietary at this point and
will not be discussed.
ƒ
The BR and BD boards are functionally the same, but the circuitry is
slightly different. These boards plug into the A board and are replace-
able. The pin out of their connectors remains the same.