Sony WLL-CA55, Руководство по обслуживанию

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1-10 (E)
WLL-CA55
Earphone Circuit
The AUDIO 1, AUDIO 2 and intercom signals can be
output to the earphone. The intercom signal is the one that
is output to the INTERCOM connector (5-pin XLR).
Multiple signals out of these three signals can be specified
at a time by the menu as output signal(s) to the earphone.
The specified signals are mixed and output to the ear-
phone. The output level is controlled in conjunction with
the intercom signal control, and then is controlled irrespec-
tive
of the intercom output with the menu.
Serial Data from WLL-RX55
This unit receives the following signals from WLL-RX55
as serial data using the wireless microphone system.
The signals are multiplexed digital data that is converted to
an audio band.
. Digitally compressed intercom signal
. 700 protocol data
.
Tally signal and CALL signal
The serial data is transmitted to this unit as “SLOT-IN
MIC” signal that is input to the APR board through the 15-
pin TUNER connector or “AUDIO1” signal that is input to
the APR board through the AUDIO 1 XLR connector.
Either one is specified by the menu and selected by IC203
and IC213 on the APR board. The selected signal is
amplified to 500 - 900 mVpp by IC208 and then trans-
ferred to the IF board through the 15 kHZ LPF.
On the IF board, the data WRR is A/D converted by
IC502, and then separated into intercom signal, 700
protocol signal, tally signal, and CALL signal by the
FPGA IC501. The intercom signal is decompressed by the
DSP IC901 and returned to the FPGA.
The decompressed serial digital intercom signal is sent to
the APR board as “INCOM CCU DAT” (on the APR
board “SDATA”) toward this unit from WLL-RX55.
The 700 protocol data is used for system control. The tally
signal is used as red/green tally display in this unit and is
transmitted to the camera. The CALL signal is merged
with the serial data on the VPR board and transmitted to
the camera. The CALL signal is merged to the 700 proto-
col data to be sent back to WLL-RX55.
Power Supply
The APR board has two DC-DC converters for self-power
supply except for a part of control block.
The power supply generates
+
7.5 V,
_
7.5 V,
+
12 V (MIC
POWER), and + 48 V (MIC POWER).
The + 7.5 V and _ 7.5 V are supplied to the RX-91 board,
and the
+
7.5 V is fed to the wireless microphone system
via the 9-pin TUNER connector. The +7.5 V and
_
7.5 V
are fed to the VPR board to be used for analog circuits.
Each output is provided with a protective circuit by means
of current detection to protect circuits from short-circuiting
or overload.
Return Video and Video Signal for Genlock
The VBS signal input into the SDI IN/VBS IN connector
and the character video generated on the DPR board are
switched, and then sent to the camera as a return video
signal.
Characters are merged with the video signal from the
camera in the FPGA IC200 on the DPR board. The merged
signal is D/A converted by IC603, and then transferred to
the APR board. On the APR board, either the input
character video signal or the input VBS signal is selected
and transmitted to the camera through the drive amplifier
as a return video signal to be displayed on the viewfinder.
The characters are used for a camera operator to recognize
a warning. Upon occurrence of an error message, the
camera viewfinder automatically switches to the character
video mode.
The APR board has a drive amplifier to transmit the VBS
signal from the SDI IN/VBS IN connector to the camera
for sync signal generator lock use.