Resumo do conteúdo contido na página número 1
Model DP524
Two-Channel AC-2 / AC-3
Digital Audio Decoder
Users' Manual
Resumo do conteúdo contido na página número 2
Resumo do conteúdo contido na página número 3
Users' Manual For Model DP524 AC-2 / AC-3 Two-Channel Digital Audio Decoder Dolby Laboratories Incorporated U.S.A. 100 Potrero Avenue, San Francisco, CA 94103 Tel: 415-558-0200; Fax: 415-863-1373 U.K. Wootton Bassett, Wiltshire SN4 8QJ Tel: 01793-842100; Fax: 01793-842101 DISCLAIMER OF WARRANTIES: Equipment manufactured by Dolby Laboratories is warranted against defects in materials and workmanship for a period of one year from the date of purchase. All warranties, conditions or other
Resumo do conteúdo contido na página número 4
Resumo do conteúdo contido na página número 5
TABLE OF CONTENTS SECTION 1 Introduction 1.1 Introduction ...................................................................................................1-1 1.3 Dolby AC-3 and AC-2...................................................................................1-2 1.4 Data Rates, Sample Rates and Channels .......................................................1-3 1.5 Regulatory Notices ........................................................................................1-4 SECTION 2 A
Resumo do conteúdo contido na página número 6
SECTION 6 Interface Specification and Description 6.1 DP524 Interface Specifications ..................................................................... 6-1 AES/EBU Digital Audio Output, J101 ................................................... 6-1 S/PDIF Digital Audio Output, J102 ........................................................ 6-1 Encoded Data In and Timing, J103, 37-pin D-connector:....................... 6-1 Status / Control, J104, 25-pin D-connector:..............................
Resumo do conteúdo contido na página número 7
SECTION 1 INTRODUCTION 1.1 Introduction The Dolby Model DP524 is a digital audio decoder unit supporting both Dolby AC- 2 and Dolby AC-3 digital audio coding algorithms. The unit supports up to two channels of audio. The data rates available are considerably lower than that required to convey conventional PCM data (between 40k and 384k bits/sec) yet provide exceedingly high audio quality. The unit automatically configures itself for the appropriate data rate, sample rate and algorithm type. Bot
Resumo do conteúdo contido na página número 8
1-2 1.2 Features • Automatic algorithm, data rate and sample rate selection • Dolby AC-3 audio coding algorithm from 40 kbps - 384 kbps • Mono, Dual-Mono or Stereo modes for AC-3 • Dolby AC-2 audio coding algorithm from 128 kbps - 384 kbps • Mono 2-channel modes for AC-2 • Analog outputs with 20-bit D/A converters • Digital outputs (AES/EBU and S/PDIF) • Software download capability for software upgrades • Selectable auxiliary data rates (0 - 9600 baud). • RS-232 and RS-422 serial interfaces all
Resumo do conteúdo contido na página número 9
1-3 1.4 Data Rates, Sample Rates and Channels Possible AC-3 Data Rates, Sample Rates and Number of Channels Data Rate Sample rate Channels 40 kbps 32kHz, 44.1kHz or 48kHz Set by Encoder 48 kbps 32kHz, 44.1kHz or 48kHz Set by Encoder 56 kbps 32kHz, 44.1kHz or 48kHz Set by Encoder 64 kbps 32kHz, 44.1kHz or 48kHz Set by Encoder 80 kbps 32kHz, 44.1kHz or 48kHz Set by Encoder 96 kbps 32kHz, 44.1kHz or 48kHz Set by Encoder 112 kbps 32kHz, 44.1kHz or 48kHz Set by Encoder 128 kbps 32kHz, 44.1kHz or 48k
Resumo do conteúdo contido na página número 10
1-4 1.5 Regulatory Notices FCC This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with this instruction manual, may cause harmful interference to radio
Resumo do conteúdo contido na página número 11
1-5 IEC NOTICES IMPORTANT SAFETY NOTICE This unit complies with the safety standard IEC65. To ensure safe operation and to guard against potential shock hazard or risk of fire, the following must be observed: GB o Ensure the voltage selector is set to the correct mains voltage for your supply. o Ensure fuses fitted are the correct rating and type as marked on the unit. o The unit must be earthed by connecting to a correctly wired and earthed power outlet. o The power cord supplied with this un
Resumo do conteúdo contido na página número 12
Resumo do conteúdo contido na página número 13
SECTION 2 APPLICATIONS The Dolby Model DP524 is suitable for a variety of point-to-point and point-to- multipoint digital transmission applications, including cable, telecommunications and satellite or terrestrial microwave links. The very high audio quality and low, spectrum-efficient data rates of the AC-2 and AC-3 coding process make them particularly appropriate for these applications. 2.1 Cable Whether for audio-only services or for an enhanced digital audio service accompanying video, the
Resumo do conteúdo contido na página número 14
Resumo do conteúdo contido na página número 15
SECTION 3 PRE-INSTALLATION 3.1 Unpacking Before proceeding further, be sure to inspect the outer carton for shipping damage. If there has been any penetration to the carton, be sure to inspect the unit for any physical damage in those areas. Several accessories have been provided in the packet provided with this manual. Please compare them with the following list to ensure that there are no missing items: Rack screws and washers Power cord Spare fuse 1A (Part. No. 56016) Spare fuse, 2A, used on
Resumo do conteúdo contido na página número 16
3-2 OPEN THE DOOR FUSE ACTIVE FUSE CARRIER (LOWER) Check that the fuse in the active (lower) fuse carrier is of the correct rating. A spare fuse can be stored in the upper fuse carrier position. Snap the fuse compartment door closed. Internal Fuse The switching power supply contains a separate fuse. Most fault conditions should be protected by the main fuse. The internal fuse rating is: 2 Amp, 250V, 20 mm, fast-blow. 3.4 Configuring Jumper Settings The Model DP524 includes certain user-selectabl
Resumo do conteúdo contido na página número 17
3-3 front, rear, and each of the sides of the unit. The three black screws should be reserved for affixing at the front. Note The front panel is attached to the top cover by means of 4 screws also affixing the handles. These do not need to be removed. By grasping the front panel handles, gently pull the top cover/front panel assembly forward then away towards the rear. Carefully set aside this sub- assembly. Reverse the above procedure when re-assembling the unit. 1 S101 J103 J105 J205 J209 J200
Resumo do conteúdo contido na página número 18
3-4 3.4.1 Jumpers for Encoded Data In & Timing (J103) Receive Timing J205 / Receive Data J206 [terminated] Termination resistors (150 ohms) are provided across the "RT" and "RD" inputs. These inputs are terminated in the default configuration, which should be appropriate for most applications. Certain situations may require that these inputs be unterminated (e.g., multiple inputs driven from a single output). Request to Send J207 & J208 / Terminal Ready J209 & J210 [on] Handshake signals "RS"
Resumo do conteúdo contido na página número 19
3-5 Note Switch positions 5 and 6 take on two roles: • They set the Aux Data output baud rate when S101-2 is in the Normal position and S101-4 is in the Aux Data position • They set the Download baud rate when S101-2 is in the Download position. • Their positions are immaterial when S101-2 is in the Normal position and S101-4 is in the Command position; the Command baud rate is at a fixed 9600 baud. 3.5.1 Switch nos. 1, 7 & 8 - Test Tone [down] Switch position S101-1 activates the built-in tes
Resumo do conteúdo contido na página número 20
3-6 3.5.3 Switch no. 3 - Digital Output Format Selection [up] Position this switch to corresponds to the type of digital output signal format. Refer to Section 4 for information regarding audio connections. Format S101-3 S/PDIF Down AES/EBU [Up] The switch setting selects how the digital bit stream is marked. S/PDIF is synonymous with "consumer" format, AES/EBU is synonymous with "professional" format. Note Digital audio output is fed to both the BNC and the XLR connectors of the rear of the uni
