Manuale d’uso / di manutenzione del prodotto DP524 del fabbricante Dolby Laboratories
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Model DP524 Two-Channel AC-2 / AC-3 Digital Audio Decoder Users' Manual MAIN.
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Users' Manual For Model DP524 A C-2 / A C-3 Tw o-Channel Digital Audio Decoder Dolby Laboratories Incorporated U.S.A. 100 Potrero Avenue, San Franc isco, CA 94103 Tel: 415-558- 0200; Fax: 415-863-1373 U.
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TA BLE OF CONTENTS SECTION 1 Introduction 1.1 I ntroduction ................................................................................................... 1-1 1.3 Dolby AC-3 and AC-2 ...............................................................
SECTION 6 Interface Specif ication and Description 6.1 DP524 Interface Specifications ..................................................................... 6-1 AES/EBU Digital Audio Output, J101 ................................................... 6-1 S/PDI F Digital Audio Output, J102 .
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.
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 .
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.
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.
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 .
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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.
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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.
3-2 OPEN THE DOOR ACTIVE FUSE CARRIER (LOWER) FUSE 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.
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.
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.
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.
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.
SECTION 4 INSTALLATION 4.1 Mounting The DP524 is designed for 19 inch rack mounting, but may be mounted in any plane and with any orientation. It occupies 1U (1 3/4") of space. When mounting the unit, ensure that there is air flow around it, and that it is not mounted directly above any equipment generating high amounts of heat.
4-2 For optimum immunity to radio-frequency interference, cable shields must be connected to the shells of the XLR connectors, not to pin 1. In an installation where the source is unbalanced, avoid gr.
4-3 Baud Rate S101-5 S101-6 0 Down Down 1200 Down Up 2400 Up Down 9600 Up Up Where is baud rate of the Encoder (generating the Aux data stream) is higher than the baud rate of the Decoder it is possible that data may be lost. 4.3.3 RS-422 (J106) The RS-422 connection is not supported in this product.
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SECTION 5 OPERATION Once the DP524 is installed and operational, no user-intervention is required. In normal operation, one of the Green LEDs will indicate the incoming sample rate (32kHz , 44.1 kHz or 48 kHz); the signal presence indicators will also illuminate if appropriate.
5-2 5.2 Rear Panel Level Controls Each analog output connector has a level control adjacent to it. Each analog output is adjustable (at full scale) over a range of below 0dBu to greater than +24dBu. 5.3 Test Tone Level The operating level for the test tone generator of the Model DP524 is -18dB relative to full scale.
SECTION 6 INTERFA CE SPECIFICA TION A ND DESCRIPTION 6.1 DP524 Interface Specifications AES/E B U Digital Audio Output, J101 XL R-type connector, 5V p-p ty pical, 110 Ohms. Pin Connection 1 Digital sig nal ground 2 Digital Audio + 3 Digital Audio - S/PDIF D igital Audio Output, J102 BNC-ty pe connector, 0.
6-2 Status / Control, J104 , 25-pin D-conne c tor: Pin Connection Comments 1 NC Do Not Connect 2 NC Do Not Connect 3 NC Do Not Connect 4 NC Do Not Connect 5 NC Do Not Connect 6 NC Do Not Connect 7 NC .
6-3 6.2 RS-449 Interface Description 6.2.1 Functional D escr iption The Dolby Model DP524 provide a standard RS-449 interface in the type DT mode (data and timing signals only , no handshakes) throug h 37-pin male D-connectors.
6-4 6.2.3 B ac k-to-B ac k Te sting For purposes of testing the Model DP523 and Model DP524 in a back-to-back configuration, a special cable must be constructed. Note that a DTE-to-DTE connection is not supported by the RS-449 specification. A standard 37-wire cable cannot be used to interconnect the units.
6-5 6.3 Serial Control I t is possible to command the DP524 via the RS-232 port, J 105 on the rear of the unit when the Command/Aux data switch (S101-4) is in the Up position. The communications protocol for command mode is fixed at 9600 baud, 1 stop bit, no parity .
6-6 Com m and $18: Retur n Syste m Status $FB $20 $18 0 $FD The unit returns the following byte : B7 B6 B5 B4 B3 B2 B1 B0 0 Dr_lock Sr_lock Test 48kHz 44.1kHz 32kHz Mute Each bit is returned set if the associated signal is active. Dr_lock and Sr_lock are internal signals.
6-7 This command will return $FF if the decoder is in Test Tone mode or if the decoder is in normal mode but does not have an input data clock that it can lock to.
6-8 Com m and $42: Set Com pre ssion mode $FB $20 $42 data $FD Where data is as follows: B7 B6 B5 B4 B3 B2 B1 B0 0 00000 C 1 C 0 C0 and C1 are defined as follows: C1 C0 Comment 0 0 Custom mode, no dig.
SECTION 7 DP524 SPECIFICATION Specifications 1 Italics = nomenclature for panel markings, switch labels, jumpers, LEDs, etc. All inputs and outputs are TTL compatible unless otherwise stated. Frequency Response Lower limit: 20 Hz. Upper limit varies from 8 to 20 kHz depending on algorithm.
7-2 Digital Audio Outputs AES/EBU, 3-pin XLR-type, male, balanced , 110 ohms ±5%, 5V pp nominal. S/PDIF, BNC female connector, unbalanced, 75 ohms ±5%, 0.5V pp nominal. Data Output / Command Input RS232, Male 9-pin D connector. RS-422, Female 25-pin D connector.
7-3 General Power Requirements 90-260 VAC, 50-60 Hz, 24VA Dimensions and Weight 1- ¾ x 19 x 11- ¾ inches (4.45 x 48.26 x 29.8 cm), 8.5 pounds (3.9 kg), approx. Emissions Complies with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules.
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Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il Dolby Laboratories DP524 è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del Dolby Laboratories DP524 - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso Dolby Laboratories DP524 imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul Dolby Laboratories DP524 ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il Dolby Laboratories DP524, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del Dolby Laboratories DP524.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il Dolby Laboratories DP524. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo Dolby Laboratories DP524 insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
