Sony HXCU-100 Service Manual page 43

PS-739 Board
This board generates 38 VDC/180 VDC for camera, 28 VDC for RCP, and 15 VDC for the internal CCU
power from the AC line power input, and supplies them. Commercial power source 100 to 240 VAC is
supplied from the rear AC inlet through the front AC switch. This board supplies 28 V for RCP and 15 V
for the internal CCU power by the internal LV converter. Then this board converts them to CAM38 V and
180 V by the internal HV converter and outputs 38 V fi rst, and then outputs 180 V upon receiving CAM
POWER ON from the CCU. Since this board checks the connection to the camera, it does not output 180
V while the camera is not connected.
CT-257 Board
This small board located on the PS-739 board contains an internal protective circuit, a PLD circuit for
CHU output control, and a 28 V output regulator for RCP.
AU-321 Board
This board contains tally (red/green) and status indicator LEDs, menu operation switches, intercom
switches, and a microphone amplifi er. The power, tally, status indicator LEDs (CABLE OPEN/SHORT,
MAIN POWER, CAM POWER, and NETWORK signals) are connected to the rear CN-3081 board.
The switches and potentiometers for the intercom, menu operation switches, MENU LEDs, and the rotary
encoder are connected to the SY-364 board.
Selection of the microphone amplifi er gain, BIAS power on/off, and balance/unbalance is set by the CCU
menu.
CN-3080 Board
This board, connected to the SDI-97 board with a fl exible card wire, outputs SD analog signals (PIX and
WF signals), HD/SD component signals, and HD/SD SYNC signals to external devices.
This board also outputs the stair case signal used for monitoring signals in the sequential mode on the
waveform monitor. Furthermore, this board input prompter signal from external devices, and interfaces
with the RCP through the connector. A relay to enable the easy monitoring function is provided on this
board, which is switched by the status signal sent form the DPR-300 board.
CN-3081 Board
This board contains the INCOM/TALLY/PGM, MIC REMOTE, WF REMOTE, and TRUNK connectors
for the interface with external devices.
This board supplies the front boards with 15 V as the CCU power supply generated by the PS-739 board,
and supplies the CN-3080 board with 28 V for RCP.
In addition, this board has a circuit to generate fan power voltage 12 V from 15 V as the CCU power
supply, and sends the fan power voltage to the fan.
2-17 (E)
HXCU-100