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1 I R T Electronics Pty Ltd A.B.N. 000 Hotham Parade, ARTARMON N.S.W. 0 AUSTRALIA National: Phone: (0) 99 Fax: (0) 99 9 International: sales@irtelectronics.com Web: EUROCARD AES/EBU Digital to Analogue Converter Type DAC-0 Designed and manufactured in Australia IRT can be found on the Internet at: 0-dac.ib.rev.doc Page of /0/00

2 DAC-0 AES/EBU Digital to Analogue Converter Instruction Manual This manual applies to units SN and above. Table of Contents Item Page Operational Safety Description Specifications Installation Front & rear panel connector diagrams Maintenance & storage Warranty & service Equipment return Drawing list index Operational Safety: WARNING Operation of electronic equipment involves the use of voltages and currents that may be dangerous to human life. Note that under certain conditions dangerous potentials may exist in some circuits when power controls are in the OFF position. Maintenance personnel should observe all safety regulations. Do not make any adjustments inside equipment with power ON unless proper precautions are observed. All internal adjustments should only be made by suitably qualified personnel. All operational adjustments are available externally without the need for removing covers or use of extender cards. 0-dac.ib.rev.doc Page of /0/00

3 Description. The IRT DAC-0 is an AES/EBU digital to analogue converter, with two stereo analogue audio outputs, and six digital AES/EBU monitor outputs from a non-reclocking distribution amplifier for the AES/EBU digital signal. The DAC-0 will operate at,. and KHz. The digital input can be ohm coax or 0 ohm balanced line with both input types available on the rear assembly and selection of the required input by links on the main circuit board. The two stereo analogue outputs are low impedance ohms sourcing and the digital outputs can be ohm coax or 0 ohm balanced line depending on the rear assembly used. The DAC-0 is designed to fit the IRT range of eurocard mounting frames, including the slot FR-00 and slot FRU-00 rack mounting frames. Circuit Description. The DAC-0 input circuit is a linking arrangement (SW,SW) to select either the balanced or unbalanced input from the rear panel input connector. The signal is then coupled to a high speed differential line receiver using transformer T. The line receiver is buffered by its internal line driver circuit and this signal drives output line driver circuits for the seven digital outputs from the DAC-0, six to the rear panel assembly via transformers T- T and one to the front panel monitor connector. The six outputs to the rear panel are sourced through ohms resistors to set the output impedance for the balanced output circuits when using the ZAC- rear panel assembly. For ohms output circuits the ZAC-0 rear panel assembly uses a resistive voltage divider to set the output impedance back to ohms at a nominal level of Vp-p. The front panel of the DAC-0 provides led indicators for the presence of audio signal in each stereo channel, loss of input digital signal, presence of dc power and a BNC jack for monitoring the digital AES audio stream. The digital to analogue converter circuit uses the Crystal CS (U9) digital audio interface receiver and the CS9 (U0) stereo digital to analogue converter. The circuit is wired to provide automatic selection of the deemphasis filter of the CS9 when the emphasis information is included on the channel status of the AES data stream. Link LK when closed will enable the auto mute function of the CS9 to mute the analogue outputs when no EAS data signal is present. The error flag from the CS is used to provide a front panel indication of loss of AES data signal. A six pole butterworth low pass filter circuit U to U follows the CS9 digital to analogue converter to remove the over- sampling noise present on the output signal of the CS9, this is followed by the gain controls RV, RV and a buffer amplifier before the balanced output amplifiers U to U9. The outputs of the low pass filters, before the gain controls RV and RV are wired to a audio level detector circuit U0which is part of the front panel assembly of the DAC-0, this provides visual indication on the front panel using led lamps of the presence of audio signals greater than 0dBFS as set by RV0. The power supply comprises two bridge rectifiers whose rectified outputs are paralleled (positive and negative respectively) to provide redundancy. The inputs to these rectifiers are two independent feeds of Vac (centre tap grounded). A DC-DC converter module is used to provide the required volts supply for the digital circuits. The DC indicator LED on the front panel is used to indicate presence of the volts supply. Three terminal regulators are used to provide the +/- volts supplies for the analogue circuits comprising operational amplifiers U to U9. 0-dac.ib.rev.doc Page of /0/00

4 DAC-0 Specifications Inputs Type x 0 Ω balanced. or x Ω unbalanced. selected by link on PCB. Format AES-99 standard. Input level 00 mvp-p minimum. Input cable length >00m Belden () >00m 0 Ω (AES digital high quality shielded pair). Outputs AES/EBU Rear panel type ZAC-0 Ω unbalanced >Vp-p. or Rear panel type ZAC- 0 Ω balanced >Vp-p. Front panel monitoring x Ω unbalanced. Format AES-99 standard. Performance Frequency range Output signal rise and fall times Analogue: Number Type,. or KHz. <0 ns. stereo Ω balanced. Performance Frequency range,. or KHz. Output level for full code + dbu (variable by internal factory preset) Frequency response +/-0. db 0 Hz to KHz. +/-0. db KHz to 0 KHz. THD+N <0.0% Noise -00 dbfs ( A weighted with idle channel, input all zeros) Linearity,+/-0. db at 90 dbfs. De-emphasis automatic from channel status. Power requirement per unit V-0-Vac < VA Connectors Unbalanced Balanced Operating temperature range Mechanical Finish: Front panel Rear assembly Standard accessories Optional accessories BNC. Phoenix terminal plug-in screw terminal blocks. 0-0 C ambient HP x U x 0 mm IRT Eurocard Suitable for mounting in IRT 9" rack chassis types FR-00 & FRU-00. Grey powder coat, silk-screened black lettering & red IRT logo Detachable silk-screened PCB with direct mount connectors to Eurocard and external signals Operation manual TME- module extender card Due to our policy of continuing development these specifications are subject to change without notice. 0-dac.ib.rev.doc Page of /0/00

5 Installation Pre-installation: Handling: This equipment may contain or be connected to static sensitive devices and proper static free handling precautions should be observed. Where individual circuit cards are stored, they should be placed in antistatic bags. Proper antistatic procedures should be followed when inserting or removing cards from these bags. Power: AC mains supply: DC supply: Earthing: Ensure that operating voltage of unit and local supply voltage match and that correct rating fuse is installed for local supply. Ensure that the correct polarity is observed and that DC supply voltage is maintained within the operating range specified. The earth path is dependent on the type of frame selected. In every case particular care should be taken to ensure that the frame is connected to earth for safety reasons. See frame manual for details. Signal earth: For safety reasons a connection is made between signal earth and chassis earth. No attempt should be made to break this connection. Installation in frame or chassis: See details in separate manual for selected frame type. Signal Connections Signal connections are made to the connectors on the selected rear panel of the DAC-0. The input signal can be either ohms unbalanced terminating or 0 ohms balanced terminating, the input selection is done be links SW,SW on the module pcb near pin of the input connector. Move the links provided to the or 0 positions marked on the board as required. The input signal is then connected to the appropriate input connector on the rear panel. For unbalanced ohms output circuits use the ZAC-0 rear panel and for balanced 0 ohms output circuits use the ZAC- rear panel assembly. The presence of AES signal at the output of the ZAC-0 can be monitored using the front panel monitoring BNC socket provided. RV and RV the analogue audio gain controls are factory preset to give a audio output level of + dbu for a 0 dbfs AES digital input signal. LK selects the auto mute function of the CS9 D/A converter, the factory setting is ON. RV0 on the front panel set the threshold for the audio presence indicator LEDs on the front panel. The factory setting is for a 0 dbfs digital input signal. Diagrams are provided giving details of the circuits of the DAC-0. 0-dac.ib.rev.doc Page of /0/00

6 NOTE: If it is necessary to remove a component from the circuit board during maintenance IT IS ESSENTIAL TO ADD SOME SOLDER TO THE COMPONENT SOLDER JOINTS BEFORE REMOVAL IS ATTEMPTED. This will add some solder flux to the joint and allow the heat from the iron to flow quickly into the joint and prevent localised overheating and damage to the circuit board. Rear assemblies may be removed for maintenance. Make sure that extraction force is applied equally and steadily at the top and bottom of the rear assembly. SHOULD THIS NOT BE DONE THERE IS A GOOD CHANCE THAT YOU WILL BEND THE MODULE CONNECTOR PINS making it very difficult to re-install the rear assembly. Front & rear panel connector diagrams The following front panel and rear assembly drawings are not to scale and are intended to show relative positions of connectors, indicators and controls only. DAC-0 DATA OUTPUT MON DC L AUDIO R LOSS N0 LEFT AES O/P's Ohm INPUT ZAC-0 RIGHT 0 Ohm LEFT AES O/P's Ohm INPUT ZAC- RIGHT 0 Ohm 0-dac.ib.rev.doc Page of /0/00

7 Maintenance & storage Maintenance: No regular maintenance is required. Care however should be taken to ensure that all connectors are kept clean and free from contamination of any kind. This is especially important in fibre optic equipment where cleanliness of optical connections is critical to performance. Storage: If the equipment is not to be used for an extended period, it is recommended the whole unit be placed in a sealed plastic bag to prevent dust contamination. In areas of high humidity a suitably sized bag of silica gel should be included to deter corrosion. Where individual circuit cards are stored, they should be placed in antistatic bags. Proper antistatic procedures should be followed when inserting or removing cards from these bags. Warranty & Service Equipment is covered by a limited warranty period of three years from date of first delivery unless contrary conditions apply under a particular contract of supply. For situations when No Fault Found for repairs, a minimum charge of hour s labour, at IRT s current labour charge rate, will apply, whether the equipment is within the warranty period or not. Equipment warranty is limited to faults attributable to defects in original design or manufacture. Warranty on components shall be extended by IRT only to the extent obtainable from the component supplier. Equipment return: Before arranging service, ensure that the fault is in the unit to be serviced and not in associated equipment. If possible, confirm this by substitution. Before returning equipment contact should be made with IRT or your local agent to determine whether the equipment can be serviced in the field or should be returned for repair. The equipment should be properly packed for return observing antistatic procedures. The following information should accompany the unit to be returned:. A fault report should be included indicating the nature of the fault. The operating conditions under which the fault initially occurred.. Any additional information, which may be of assistance in fault location and remedy.. A contact name and telephone and fax numbers.. Details of payment method for items not covered by warranty.. Full return address.. For situations when No Fault Found for repairs, a minimum charge of hour s labour will apply, whether the equipment is within the warranty period or not. Contact IRT for current hourly rate. Please note that all freight charges are the responsibility of the customer. The equipment should be returned to the agent who originally supplied the equipment or, where this is not possible, to IRT direct as follows. Equipment Service IRT Electronics Pty Ltd Hotham Parade ARTARMON N.S.W. 0 AUSTRALIA Phone: 99 Fax: service@irtelectronics.com 0-dac.ib.rev.doc Page of /0/00

8 Drawing List Index Drawing # Sheet# Description 09 DAC-0 AES/EBU distribution amplifier 09 DAC-0 AES/EBU distribution amplifier 09 DAC-0 AES/EBU distribution amplifier 09 DAC-0 AES/EBU distribution amplifier 0 issue DAC-0 front panel sub-board (early version) 0 issue DAC-0 front panel sub-board (later version) 09 ZAC-0 ohms unbalanced rear assembly 099 ZAC- 0 ohms balanced rear assembly 0-dac.ib.rev.doc Page of /0/00

9 PL/a,b PL/a,b PL/9b R R9 C0 T U C9 L uf + C 00nF PL/9a PL/b 00nF 0 R 0 PL/ DAC-0 EAS/EBU D-A CONVERTER Title SIZE A COPYRIGHT DO NOT COPY NOR DISCLOSE TO ANY THIRD PARTY WITHOUT WRITTEN CONSENT DRAWN K.N SCALE Sheet Drawing No. 09 N.T.S. of CHECKED ENG. APP. IRT Electronics Pty. Ltd. ARTARMON NSW AUSTRALIA 0 Revision: -Feb-00 Date: BAL I/P D BAV99 UNBAL I/P SW PL/0a,b PL/a,b PL/b PL/a PL/b PL/a PL/a,b PL/a,b PL/b PL/a PL/9b PL/9a PL/a,b PL/0a,b V++ V++ V-- PL/a,b PL/a,b PL/a,b PL/a,b PL/a,b C PL/a,b C 00nF T PL/9a,b PL/0a PL/0b PL/a PL/a PL/b PL/b AES MON. ERROR LED L AUDIO R AUDIO V-- FRONT PANEL (0) U C T PL/a 0uF C R R C T 00nF U C9 D BAV99 SW uf R 00nF C T R 0R0 R R uf LK9 C S AUDIO DS9 uf C R9 R R T U C0 uf 00nF C T9 R R9 uf + C 00nF DS9 C R 0R0 C 00nF C 00nF R9 0 U C R C0 C0 uf R0 0 00nF FL DS9 FL C 00uF CONV ZS +V VIN+ C 00nF ZD N C 0nF C 00uF FL -V VIN- FL PL R0 R uf DS9 R 00 R 00 DS9A R 0 + C 0uF C 00nF L L C 00nF DB F R F R DB0 R R DB F R R R F R DB0

10 +V SIZE Title DAC-0 R 0K R 0K A AES/EBU D-A CONVERTER SCALE Sheet Drawing No. 09 N.T.S. of IRT Electronics Pty. Ltd. ARTARMON NSW AUSTRALIA 0 9 LK + 0 UC + C0 HC C0 +V C 0nF 00nF +V C uf C uf R 0K 00nF LK UD L L +V C C9 C9 HC uf uf +V uf C C +V +V C C LK R9 K +V PL/ +V COPYRIGHT DO NOT COPY NOR DISCLOSE TO ANY THIRD PARTY WITHOUT WRITTEN CONSENT DRAWN K.N S AUDIO AOUTR+ 00nF AOUTR- AOUTL- AOUTL+ 00nF R 0K R 0K 00nF 00nF R9 0K R0 0K VD+ VA+ DEM DEM0 LK DIF0 0 FSYNC M0 M M M A-MUTE VD+ VA+ LK DIF 9 LK SCK R AOUTR+ DIF LK SDATA SC/FCK MUTE_R U0 CS90-KS LRCK C U9 CS SEL LK MUTE_L MCLK U RX+ 9 C R SCLK 9 CBL AOUTL- AOUTR- RX- 0 K R0 00nF AOUTL+ DGND AGDN SDATA 0 0R0 ERF R 0 VERF CE/F CD/F CC/F0 CB/E CA/E C0/E0 DGND MCK RLT AGND C 00nF FB CHECKED ENG. APP. Revision: -Feb-00 Date: 9 0 R K C nf R C 90 Q BC R 00nF 0K UA HC D BAS L + C C 00nF 0uF UB HC ECR

11 +V +V C C0 C0 PL/ 00nF C R R 00nF C R C R90 9K C K K 0uF 00 0pF 0pF 0pF R K 0pF R R R R0 K R K K 9K C C n K C 0pF R R AOUTR+ K K C9 C uf RV 0K C9 0pF R9 K R9 K R K C 0pF 00nF 00nF -V -V +V +V C C C0 R R0 R C0 PL/ 00nF C0 C 00nF C R K R AUDIO L AUDIO SIZE Title A DAC-0 EAS/EBU D-A CONVERTER LOW PASS FILTERS SCALE Sheet Drawing No. 09 N.T.S. of IRT Electronics Pty. Ltd. ARTARMON NSW AUSTRALIA 0 UA UB UA UB RV 0K MC0D MC0D MC0D MC0D 0uF 00 9K 0pF R K K 0pF UA R0 R9 R 0pF UA R K 0pF R0 K UB AOUTR- AOUTL- K 9K R R C C9 n K C 0pF UB RV 0K MC0D MC0D MC0D AOUTL+ K K MC0D C C uf RV 0K C 0pF R K R K R K C 0pF 00nF 00nF -V -V COPYRIGHT DO NOT COPY NOR DISCLOSE TO ANY THIRD PARTY WITHOUT WRITTEN CONSENT DRAWN K.N. CHECKED ENG. APP Revision: -Feb-00 Date: ECR

12 O/P O/P C9 pf C9 pf +V -V R9 K +V C9 R K C9 0uF C 0uF +V C R 00nF R9 00nF UA R9 UA R00 K99 PL/b - PL/b - K99 NE NE R9 K C R9 K C9 00nF 00nF -V -V C9 pf C90 pf R K R9 K R9 R R99 R9 + PL/a K99 + PL/a K99 R AUDIO R9 0K R 0K C0 pf C0 pf R K +V C0 SIZE Title A DAC-0 EAS/EBU D-A CONVERTER ANALOGUE OUTPUTS SCALE Sheet Drawing No. 09 N.T.S. of IRT Electronics Pty. Ltd. ARTARMON NSW AUSTRALIA UB UB NE NE R0 K +V C9 R 00nF U9A R R09 00nF UA R0 PL/b K99 PL/b K99 NE C0 R K NE C9 R0 K 00nF 00nF -V -V C00 pf C0 pf R0 K R K + R U9B R PL/a + K99 PL/a NE UB R0 R0 K99 L AUDIO R0 0K R0 0K NE COPYRIGHT DO NOT COPY NOR DISCLOSE TO ANY THIRD PARTY WITHOUT WRITTEN CONSENT DRAWN K.N. CHECKED ENG. APP Revision: -Feb-00 Date:

13 +V SIZE A TITLE DAC-0 FRONT PANEL SUB-BOARD +V +V SCALE DRAWING No. R0 0 0 IRT Electronics Pty. Ltd. ARTARMON NSW AUSTRALIA 0 SHEET OF +V C0 +V LD LDGRN 'DC' LD LDRED 'ERROR' 0uF U0 TSM9 SK0 V+ V+ MODE R HI 9 MODE R HI 9 LD0 REF REF LD9 +V ADJ ADJ +V R LO LD0 LD9 +V VLED C0 0uF R0 90 'AES MON.' SK0 U0 TSM9 C0 0nF VLED R0 R C0 0uF R0 R0 K K R0 R0 R LO R0 C0 0nF K R K LD IN 0 LD IN 0 V- C0 0uF V- COPYRIGHT DO NOT COPY NOR DISCLOSE TO ANY THIRD PARTY WITHOUT WRITTEN CONSENT R0 0K R09 0K K.N. DRAWN CHECKED ENG. APP. CONTRACT No. DISRIGHT DISLEFT /0/9

14 +V +V R0 0 R0 90 'AES MON.' SIZE Title A DAC-0 Front Panel Sub-Board SCALE Sheet Drawing No. 0 N.T.S. of IRT Electronics Pty. Ltd. ARTARMON NSW AUSTRALIA 0 +V +V LD LDGRN 'DC' LD LDRED 'ERROR' SK0 +V LD LDGRN SK0 R09 MEG R0 K U0D R0 R U0B 0 0 +V +V K LM9M LM9M C0 00NF +V 'L AUDIO' +V C0 0nF R0 K C0 0UF C0 0nF C0 0UF R K RV0 K +V +V R 0K +V LD LDGRN C0 R0 K R0 MEG R 0NF U0A U0C 9 K R0 LM9M LM9M 'R AUDIO' C0 00NF 0 +V R0 K COPYRIGHT DO NOT COPY NOR DISCLOSE TO ANY THIRD PARTY WITHOUT WRITTEN CONSENT DRAWN K.N. CHECKED ENG. APP Revision: -Feb-00 Date: -0-99

15 a b a b a b a b a b a b a b a b 9a 9b 0a 0b a b a b a b a b a b a b a b a b 9a 9b 0a 0b a b a b a SIZE b a TITLE b a ZAC-0 SK R AUDIO O/P SK L AUDIO SK R AUDIO O/P SK L AUDIO SK R0 R R 0R SK R R R 0R J OPTIONAL POWER IN b a b SK0 OHMS REAR ASSEMBLY FOR DAC-0 a b 0 OHMS INPUT a b 9a 9b 0a SK9 0b OHMS INPUT a b a b R 0R C 0N J PIN DIN RECEPTACLE COPYRIGHT DO NOT COPY NOR DISCLOSE TO ANY THIRD PARTY WITHOUT WRITTEN CONSENT K.N. SCALE DRAWING No. 09 IRT Electronics Pty. Ltd. ARTARMON NSW AUSTRALIA 0 DRAWN CHECKED PCB 00R/A ENG. APP. CONTRACT No. SHEET OF /0/9

16 a b a b a b a b a b a b a b a b 9a 9b 0a 0b a b a b a b a b a b a b a b a b 9a 9b 0a 0b SIZE TITLE ZAC- a 0 OHMS REAR ASSEMBLY FOR DAC-0 SK R AUDIO O/P SK L AUDIO SK R AUDIO O/P SK L AUDIO SK SK b a b a b a J b a SCALE OPTIONAL POWER IN b a b SK0 a b 0 OHMS INPUT a b 9a 9b 0a SK9 0b OHMS INPUT a b a b R 0R C 0N J PIN DIN RECEPTACLE COPYRIGHT DO NOT COPY NOR DISCLOSE TO ANY THIRD PARTY WITHOUT WRITTEN CONSENT DRAWING No. 099 IRT Electronics Pty. Ltd. ARTARMON NSW AUSTRALIA 0 SHEET K.N. DRAWN CHECKED ENG. APP. CONTRACT No. OF /0/9 PCB 00R/B

IRT Eurocard Types. (/xxx = /APC or /PC) DANGER. Invisible LASER radiation- Avoid direct exposure to beam. Class 1 LASER Product

IRT Eurocard Types. (/xxx = /APC or /PC) DANGER. Invisible LASER radiation- Avoid direct exposure to beam. Class 1 LASER Product I R T Electronics Pty Ltd A.B.N. 000 Hotham Parade, ARTARMON N.S.W. 0 AUSTRALIA National: Phone: (0) 99 Fax: (0) 99 9 International: + 99 + 99 9 Email: sales@irtelectronics.com Web: www.irtelectronics.com