SONY BVW-55
Manual de Servicio

(2) Audio Signal Processing System (CP-316, APR-42, SDI-23, AFM-16, AU262, HP-88)
Recording system The analog audio signals (CH1 and CH2) input to the AUDIO INPUT connectors (on the CP-316 board) is input by the CP-316 board and sent to the APR-42 board. In the CP-316 board, the Phantom power is supplied only for overseas models. The SDI signal input to the SDI INPUT connector is sent to the SDI-23 board, and serial/parallel converted. After the SDI audio signal is extracted by the audio Rx TBC block, the SDI audio signal is converted to serial, and sent to the APR-42 board. In the APR-42 board, the SDI input audio signal sent from the SDI-23 board is D/A converted, switched with the analog input signal sent from the CP-316 board, channel switched, channel mixed, and level controlled, etc. Then, the CH-1 and CH-2 audio signals are sent to the AU-262 board while the CH-3 and CH-4 audio signals are sent to the AFM-16 board. The audio signals (CH-1/CH-2) input to the AU-262 board are subject to DOLBY NR processing and waveform equalization after passing through the AGC/limiter circuit. They are then superimposed with the bias signal, and recorded on tape as the longitudinal audio signal. On the other hand the audio signals (CH-3/CH-4) input to the AFM-16 board are passed through the limiter circuit after NR processing, and then FM modulated. They are then sent to the RP-107 board as the AFM RF signal.

Playback system The longitudinal audio signals (CH-1/CH-2) play backed by the AT head are waveform equalized and DOLBY NR processed in the AU-262 board, and then level-controlled by the AFM-16 board. The C RF signals sent from the RP-107 board is subject to AGC in the AU-262 board, and after only the AFM audio signals (CH-3/CH-4) are demodulated, NR processing and level control are performed. The longitudinal audio signals and AFM audio signals which are level-controlled are sent to the APR-42 board. After the audio channel signals for line output and monitor output are selected, they are sent to the CP-316 board, and output from the connector panel via the 600 Z driver. The audio signal for monitor output can be monitored by the headphones or speaker inside the unit. The longitudinal audio signal and AFM audio signal sent to the APR-42 board are A/D converted, sent to the SDI-23 board, and multiplexed with the video data by the SDI encoder. They are then parallel/serial converted, and output from the SDI OUT connectors on the connector panel as the SDI signal.

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BVW-55