Studer-928-Service-Manual-Section-4电路原理图.pdf

Professional Audio System Components E42Date printed: 29.11.01 Technical Specifications Audio:Power output4 W/15 5 W/8 2.5 W/4 , continuous, sine wave THD< 0.1% rated output, 30 Hz.16 kHz Frequency response0.5 dB, 30 Hz.16 kHz Input impedance10 k, balanced Sensitivity17.+16 dBu (0.11.4.9 Vrms) for rated output Maximum input level+24 dBu (12.3 Vrms) clipping point S/N100 dB, linear to 23 kHz at normal operating gain (input +6 dBu) 85 dB, at maximum gain Supply: 15 V DC (40 mA idling; 400 mA 5 W/8 ) Output stage quiescent current23 mA Dimensions: Euro-card100 160 mm, 7M units wide Weightapprox. 210 g Ordering Information: 5 W amplifier withtransformerless input1.915.410.xx input transformer1.915.411.xx transformerless input and remote muting facility1.915.412.xx input transformer and remote muting facility1.915.413.xx transformerless input and remote gain control (VCA)1.915.414.xx input transformer and remote gain control (VCA)1.915.415.xx RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 Professional Audio System Components Date printed: 29.11.01E43 2.2.7 40 W Power Amplifier1.915.440/441 For applications where higher power level is needed, a 40 W amplifier has been realized on a Euro-card. Its width is 32 mm, which equals 7M widths approximately. Power is supplied from a separate 45 VDC source, as is contained in the 19” mounting frame 1.918.120.xx. Two amplifier cards will fit into that frame, making it suitable for applications where stereophonic monitoring is required. Special FeaturesTransformerless version with electronically balanced inputs standard Version with balanced and floating inputs available Output stage protected from overload by momentary power limiting Temperature sensing avoids thermal overload High-end frequency response limited to prevent transient intermodulation distortion Low distortion performance, even at low power output Operation with output transformer possible Professional Audio System Components E44Date printed: 29.11.01 Technical Specifications Audio:Power output40 W/4 , continuous, sine-wave, THD 50 dB, 30 Hz.16 kHz (with input transformer) Input sensitivity 12.+18 dBu (0.195.6.2 Vrms) for rated output (adjustable with jumper in three 10 dB-increments, plus fine-trim range of 12 dB) Frequency response+0.5/1 dB, 30 Hz.15 kHz S/N105 dB maximum gain 90 dB minimum gain Supply:45 VDC (70 mA idling, 1.5 A 40 W/4 ) Dimensions:Euro-card100 160 mm, 7M units wide Ordering Information: Euro-cards40 W power amplifier with transformerless input1.915.440.xx 40 W power amplifier with input transformer1.915.441.xx 19”/1U standard products 40 W power amplifierMono version, 19”/1U75.700.80311 Stereo version, 19”/1U75.700.80322 19”/1U mounting frame (without amplifier cards)1.918.120.xx Professional Audio System Components Date printed: 29.11.01E45 2.2.8 Monitor Switching Relays1.915.601/602 Two different monitor circuit switching cards are available. They are equipped with either five or eight relays for switching of a corresponding number of stereo sources to one or two stereo outputs in monitor circuits. The relays are available with coil ratings of 6 VDC or 24 VDC, depending on the users requirement. Click-suppressing diodes are wired across each relay coil. The relays are equipped with four double throw (change-over) contacts each. Isolation of the monitor lines from external circuitry is achieved by 5.6 k resistors in the “a” and “b” legs of each stereo line, thus a high imped- ance (bridging) load is presented to the outside source, even in de- energized (non-selected) status, when the respective pair of relay contacts shorts the lines after the respective isolation resistors. With a relay ener- gized, the corresponding stereo pair is routed to a stereo bus available on four pins of the 32-contact edge connector (in case of the 5-input card 1.915.601.xx). Professional Audio System Components E46Date printed: 29.11.01 Card 1.915.602.xx features a similar circuit configuration with eight relays, to switch one unbalanced and three balanced stereo inputs. Two stereo buses appear on eight pins of the edge-connector; in this way, the four in- puts can be switched to either one or to both outputs, such as may be the case with separate monitor circuits in the control room and in the studio. Dimensions:Euro-card100 160 mm, 4 M units wide Weightapprox. 250 g Ordering Information:Relay card, 5 IN/1 OUT1.915.601.xx Relay card, 4 IN/2 OUT1.915.602.xx Professional Audio System Components Date printed: 29.11.01E47 2.2.9 Transistor-Driven Relays (7+2)1.915.603 This Euro-card is supplied with nine transistor-driven relays with single- pole, double-throw (SPDT) contacts. For two of the relays, both nor- mally-open and normally-closed contacts are routed to the edge connector; for the remaining seven it is jumper-selectable whether the normally-open or the normally-closed contact is used. The relays are designed for operation on 6 VDC, and each relay coil is bridged with a click-suppressing diode. PNP transistors in series with the coils are blocking the current flow, because each transistor is normally bi- ased off. By applying the output from the gate of an external control logic to the base of a transistor, it is switched into saturation, thereby energizing the respective relay. This arrangement of nine relays was designed for use in signaling systems within a studio installation; however, it may find its use for other applications as well. Polarity of the relays supply voltage must be observed when utilizing this circuit. 10k 4k7 MAKE OR BREAK CONTACTS (7 ) 6 V CHANGE-OVER CONTACTS (2 ) 10k 4k7 6 V Professional Audio System Components E48Date printed: 29.11.01 Technical Specifications Contact Ratings:max. 1 A/30 VDC or 0.3 A/125 VAC Note:In this application 48 V must not be exceeded to avoid shock hazard. Switching power60 VA (AC) 100 W (DC) Dimensions:Euro-card100 160 mm, 4 M units wide Ordering Information:Transistor-driven relays1.915.603.xx Professional Audio System Components Date printed: 29.11.01E49 2.2.10 Dual Limiter1.915.700 In sound work there are numerous situations where the signal amplitude has to be limited to a pre-determined level in order to prevent overloading of succeeding equipment, such as light modulators in film work, or radio transmitters. With this limiter, excessive levels are automatically reduced to a preset level, and, since regulation is controlled by the programs en- ergy content, the performance of this limiter is free of any “pumping” ef- fects. Gain reduction is achieved with a Studer Voltage Controlled Ampli- fier (VCA) which ensures low noise performance and negligible distor- tion. Two identical, independent limiter circuits are contained on one Euro- card, plus additional, separate gain stages to drive peak program meters. The perfect tracking of the two VCAs makes this Dual Limiter suitable for stereo work as well, in which case a simple electrical connection is needed to link the units. Note:Gain reduction meters (not supplied) can be connected to the LINK out- puts as well, if required. Professional Audio System Components E50Date printed: 29.11.01 Technical Specifications Input:Impedance5.4 k, balanced configuration 2.7 k, unbalanced configuration Overload point+20 dBu (7.75 Vrms) Output:Impedance< 50 , unbalanced Frequency response+0/0.5 dB, 30 Hz.15 kHz +0/3 dB, 2 Hz.200 kHz Gain0 dB, limiter off Output noise level102 dBu, Limiter on 106 dBu, Limiter off Limiting ratio20:1 Threshold15 dBu.+3 dBu, adjustable Limited output level14 dBu.+4 dBu, depending on threshold setting Attack time1 ms Release time50 ms.5 s, program-dependent PPM Section: Output impedance 10 k Clipping point+24 dBu (12.3 V) Common mode rejection 50 dB, unbalanced to ground Output:balanced and floating Minimum permissible load200 Maximum output level +24 dBu (12.3 V) Frequency response0.2 dB, 30 Hz.60 kHz, equalization off THD 96 dB, equalizer off 93 dB, equalizer on (linear) Supply:15 V (80 mA idling, 170 mA +24 dBu into 200 ) Dimensions:Euro-card100 160 mm, 8 M units wide Ordering Information: Euro-cards:Line equalizer, horizontal, for recessed mounting1.915.776.xx Line equalizer, vertical, for recessed mounting1.915.777.xx Line equalizer, vertical, for flush mounting (ELMA)1.915.779.xx 19” standard productMounting frame (19”/1U) with power supply and front panel, wired for three equalizer cards 1.915.776 (not incl.)1.918.117.xx Professional Audio System Components E56Date printed: 29.11.01 2.2.13 Dual Balancing Unit/Dual Line Amplifier1.915.904 In professional audio work it is not uncommon that equipment with un- balanced input or output configuration must be connected to a system that is based on a strictly balanced design. The Dual Balancing Unit is the ideal component if the requirement of matching unbalanced to balanced equip- ment or vice versa has to be satisfied. The Dual Balancing Unit consists of one Euro-card which contains four separate circuits to accommodate unbalanced-to-balanced or balanced-to- unbalanced matching in a stereo system. It is the ideal choice for applica- tions in which consumer-type stereo equipment has to be integrated into a professional audio system, where balanced audio lines are a must. The Dual Balancing Unit will also be used in situations where balanced auxil- iary units must be connected to unbalanced insert points on a mixing desk. Professional Audio System Components Date printed: 29.11.01E57 The use of the balancing unit is not restricted to matching of balanced and unbalanced audio system components, because it can also be utilized as a (line) booster amplifier or as a stereo-to-mono mixer. By simply connec- ting the unbalanced outputs and inputs together and by adjusting again within the available ranges, two booster amplifiers with a maximum gain of 30 dB and a maximum output capability of +24 dBu*) can be realized. For stereo-to-mono mixing, the unbalanced sides of the amplifier sections simply are connected by means of combining (mixing) resistors, as shown in the diagram below. *)To avoid signal clipping, a system should always be designed in such a way that signal peaks stay well below an amplifiers maximum output ca- pacity. Alignment procedures and level settings depend to a large degree on the type of metering used in an audio system. When making measure- ments with a steady-state signal, a margin of 6 dB below a systems clip- ping point and the PPM deflected to “zero volume”, or a margin of 15 dB (for programs with extreme crest factors, even 20 dB) when utilizing a VU-meter, is considered good engineering practice. Professional Audio System Components E58Date printed: 29.11.01 Technical Specifications Balanced to unbalanced (Section 1): Input impedance 10 k, balanced/floating Maximum input level+24 dBu Output impedance 100 dB; attenuation set to 6 dB, line level +6 dBu Unbalanced to balanced (Section 2): Input impedance5 k, unbalanced Maximum input level+20 dBu Output impedance 50 , balanced/floating Minimum load200 Maximum output level+24 dBu Frequency response0.2 dB, 30 Hz.16 kHz Gain14/30 dB; two fixed steps 0.17 dB; variable S/N 100 dB; gain set to 6 dB, line level +6 dBu Supply:15 V (70 mA, idling; 170 mA, each channel +24 dBu into 200 ) Dimensions:Euro-card100 160 mm, 7 M units wide Ordering Information: Euro-card:Dual balancing unit1.915.904.xx 19”/1U standard products:2CH balancing unit (1 1.915.904)75.700.89212 4CH balancing unit (2 1.915.904)75.700.89422 6CH balancing unit (3 1.915.904)75.700.89632 Professional Audio System Components Date printed: 29.11.01E59 2.3 Racks and Frames 2.3.1 19” Mounting Frame for 3 Euro-Cards1.918.100 This 19” mounting frame (height: 44.5 mm/1U) offers space for three Euro-cards next to the power supply. The power supply provides 15 VDC (regulated) and 24 VDC (unregulated). The frame comes equipped with three edge connectors to accommodate three Euro-cards horizontally, side by side. A blank back panel of ano- dized aluminium is provided and permits the installation of input and out- put connectors as required, depending on the application. Professional Audio System Components E60Date printed: 09.01.02 Technical Specifications Primary:Voltage selector for100, 120, 140, 200, 220, 240 VAC Fuse (slow-blow)400 mA (for 100.140 VAC) 200 mA (for 200.240 VAC) Secondary:Regulated voltage15 VDC, 0.5 A max. Unregulated voltage24 VDC, 0.2 A max. (for signaling) Fuses (slow-blow)2 1 A Ordering Information: 19”/1U standard productMounting frame for three Euro-cards with power supply and stabilizer PCB, with two blank aluminium back panels (1.918.100.21)1.918.100.xx Alternative Back Panels:The mounting frame 1.918.100.xx can be equipped with the following back panels: Ordering Information: Alternative Back Panels for Mounting Frame 1.918.100 Steel back panel for 15 XLR sockets (Neutrik)1.918.113.03 Alternative Back Panels for Blank Panels 1.918.100.21 Aluminium back panel for 6 XLR sockets (Neutrik)1.918.100.36 Aluminium back panel for 1 Siemens 30/39 pin and 1 15pin D-type sockets20.020.402.00 Aluminium back panel for 2 Siemens 30/39 pin sockets1.918.100.33 Mechanical interface Siemens panel D-type connector: see chapter 2.3.4. XLRXLR 123456789101112131415MAINS 123456 XLRXLR MAINS BLANK PANEL 1.918.100.21 BLANK PANEL 1.918.100.21 1.918.100.361.918.100.33 1.918.113.03 1.918.100.01 15p D SIEMENS 30/39p 20.020.402.00 SIEMENS 30/39p SIEMENS 30/39p Professional Audio System Components Date printed: 29.11.01E61 2.3.2 19” Ventilation Unit/19” Blank Panels1.918.119/0XX When filling a cabinet rack with various electronic equipment, consider- able heat may be generated, which could be harmful to other nearby com- ponents. To provide for sufficient convection cooling, the use of ventila- tion units above and below the heat-generating equipment is strongly rec- ommended. A ventilation unit consists of a 19” wide and 1U high sheet metal struc- ture, which extends about 340 mm into the rack. The units front section is perforated, with a slanting metal panel mounted inside. By installing the ventilation unit with that panel either slanting upwards or downwards, the air flow can be directed as desired. If only moderate heat problems have to be coped with, it may be sufficient to use one ventilation unit above or below the heat source, and to provide sufficient spacing from adjacent equipment by installing a 1U blank panel on the opposite side. Ordering Information: 19” Ventilation Units Ventilation unit 19”/1U1.918.119.xx Ventilation unit without air guide panel1.918.119.09 19” Blank Panels Blank panel 19”/1U high, anodized finish1.918.001.xx Blank panel 19”/2U high, anodized finish1.918.002.xx Blank panel 19”/3U high, anodized finish1.918.003.xx Blank panel 19”/1U high, plastic coated, grey1.918.001.09 Blank panel 19”/2U high, plastic coated, grey1.918.002.09 Blank panel 19”/3U high, plastic coated, grey1.918.003.09 Blank panel