Circuit Description; Front Boards - Sony HDCU2500 Maintenance Manual

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Circuit Description

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Front Boards

AT-167A board
The AT-167A board has the built-in microprocessor (SH2-DSP). It controls various circuit boards inside this unit and
the power supply. It also performs the system setup including a camera.
The board performs command communication with a camera, and with RCP, MSU, or CNU.
Also, it enables Ethernet connection by the Ethernet controller with the built-in microprocessor.
It has the built-in signal generator circuit generating HD and SD. This signal generator circuit establishes gen-lock with
external (main) reference and also gen-lock between HD and SD. It controls phase of all video signal outputs.
It has the sync output of one channel enabling to switch between the HD ternary value sync signal and the SD sync
signal.
AVP-15 board
The AVP-15 board processes the audio signal, tally, and trunk line. It has the following functions.
• D/A-converts and outputs the MIC signals supplied from the camera in digital format.
• A/D converts the intercom signals (ENG/PROD/PGM/Front-Intercom) input to this unit.
• Inputs the intercom signals sent from the camera in digital format and the A/D-converted audio signals of this unit
to the digital mix IC, and performs line selection, mixing, and volume control.
• D/A converts the signals processed at the digital mix IC, and outputs it to external circuits.
• R/G/Y tally signal I/F
• Trunk line (RS-232C/422A) I/F
DTX-9 board
The DTX-9 board processes the return signals and the prompter signals.
This board can handle the 3G-SDI /HD-SDI/SD-SDI/VBS signals as return signals, and convert them to the specified
signals and send them back to the camera.
• Phase adjustment is performed on the 3G/ HD-SDI signal.
• The SD-SDI signal is up-converted to the pseudo-HD signal and its signal phase is adjusted.
• The VBS signal is converted to the digital signal equivalent to the SD-Digital-Component signal, and processed in
the same way as the SD-SDI signal. The signal also has the Frame conversion function and performs reverse
conversion (from 60 i to 24 PsF) according to the mainline system.
The signal input as a prompter is A/D-converted, embedded to the return signal and then sent to the camera.
DRX-9 board
The DRX-9 board processes the main-line signals from the camera.
• Phase adjustment and re-clocking using line memory
• Frame conversion (2-3 Pull Down) function as necessary
• Down-conversion function as necessary
• Has the built-in 3G/HD signal color bar generator and supports multiple formats
• Matches the MIC signal from the camera to the delay of the video signal, and then multiplexes it to the SDI signal.
HDCU2500
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