Bogen-MT125B-pa-sm维修电路图 手册.pdf

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1、A DIVISION OF LEAR SIEGLER, INC. BOOSTER AMPLIFIERS MODELS MT-60A Lo-Z 500/600 ohm with TL600 xfmr; Bridging input 1:1 with TL 100 xfmr CONTROLS AND INDICATORS Level control, illuminated power switch, speech filters OUTPUT LOADS (Const. Volt.) 25V CT, 25V, 7OV, 11OV OUTPUT LOADS (Spkr. Imp.) 8 and 1

2、6 ohms 4, 8 and 16 ohms (See chart for other impedances) (See chart for other impedances) SEMICONDUCTORS 6 Transistors, 7 Diodes 10 Transistors, 6 Diodes POWER CONSUMPTION I20VAC, 60Hz, 180 watts Rated 120VAC 60Hz, 360 watts Rated output output 120VAC 60Hz, 25 watts Quiescent 120VAC 60Hz, 45 watts Q

3、uiescent (no output) (no output) 48-56 VDC, 3 Amp Rated 48-56 VDC, 6 Amps Rated output output 48-56 VDC, 350 mA Quiescent 48-56 VDC, 600 mA Quiescent (no output) (no output) AC Circuit Breaker OVERLOAD PROTECTION Thermal Circuit Breaker Transient Protection Diodes DIMENSIONS 3.1” x 8.5” x 14” (8 x 2

4、1.5 x 36 cm) WEIGHT 18% lbs. (8.40 kg.) 5.25” x 8.5” x 15” (13 x 21.5 x 38 cm) 27 lbs. (12.3 kg.) Printed in USA 8111 54469148 RadioFans.CN COMPANION UNITS AND ACCESSORIES Model CAM CDM CSM CFC-1 RPK-37 TL100 TL600 Description and Inputs Mixer-Preamplifier, 4 Hi-Z/Lo-Z Bal MIC, 1 AUX Mixer-Preamplif

5、ier, 6 Lo-Z Bal MIC Studio Mixer, 4 Lo-Z Bal MIC 2/ 3 Octave Equalizer Rack Mounting Kit 19” x 5” (48.26cm x 17.78 cm; mounts 2 units) 1: 1 Bridging Input Transformer Line Input Transformer, plug-in, 500/600-ohm impedance High impedance input The amplifier can be driven to full output from any sourc

6、e developing 200 mV across one of the Hi-Z inputs. Wire a single- conductor, low-capacity shielded input cable to a standard phono plug (Cinch 18A, or equivalent) and connect to one of the Hi-Z jacks on the rear of the chassis. Amplifiers may also be connected in parallel by connecting a patch cord

7、from Hi-Z input to Hi-Z input of the amplifiers without loss of gain. Low impedance input The amplifier will match a low-impedance (500/600 ohm) source if a Bogen Model TL-600 transformer is installed in socket Xl on the circuit board. Connect a twisted, shielded pair (Bogen BB-8450, or equiv.) inpu

8、t cable to the BAL INPUT LOW Z terminal strip on the rear of the unit. Use the two outside terminals on the strip for input and connect the cable shield to the GND terminal. If an unbalanced input is required, connect a jumper from the GND terminal to an adjacent input terminal. CA UTION Remove all

9、power from unit transformers. before installing OUTPUT TERMINAL STRIP OF DRIVER AMPLIFIER n 74-0736-A AT 70V RI - IOK, W A T 25V RI = 3.3K,W Figure 1 -Input from another amplifier Balanced bridging input The inputs for two or more amplifiers may be paralleled without loss of gain. To do this, instal

10、l a Bogen Model TLlOO transformer in socket Xl. Connect the 6OOa source to the BAL LOW Z terminal strip on the rear of the unit. Use the two outside terminals on the strip and connect the cable shields to the GND terminal. If an unbalanced input is required, connect a jumper from the GND terminal to

11、 an adjacent input terminal. Input from another amplifier The amplifier can be driven from a standard public address amplifier that provides a 25-volt or 70-volt constant voltage output. To do this, connect the output of the amplifier to one of the Hi-Z INPUT jacks via a resistor network (see figure

12、 1). The resistors shown in figure 1 are in addition to the normal loudspeaker load on the output of the public address amplifier. OUTPUTCONNECTIONS CA UTION Be sure to foIlow 1ocaI electrical codes when connecting amplifier output. A variety of outputs is provided from the amplifier, either balance

13、d or unbalanced. Refer to Table 1 for appropriate connections. Generally, the ground link does not need to be connected unless an unbalanced output is especially desired. TABLE 1- Output Connections *110V 260 7ov 83.3 50V 42 45V - 32.5V - 31v 16 25v 8to 10.5 * 13v 2.8 12.5V 2.5 *Unbalanced output on

14、ly *Disconnect link between COM and GND OUTPUT IMPEDANCE (ohms) VOLTAGE MT 60A MT 125B 1 125 40 20 16 8to 10 - 4 to 5 1.4 1.25 1 2 3 4 5 6 7 *JUMPER1 to3OUTPUT2-7 OUTPUT 3-7 5-7 36 4-6 3-6 3-5 l-2 34 2 RadioFans.CN Figure 2 -External level control for amplifiers 70V constant-voltage output For 70V c

15、onstant voltage operation, connect the speaker leads to the 70V and COM terminals on the rear of the unit. If grounding is required, connect the link from COM to GND. 25V constant-voltage output For 25V constant-voltage unbalanced operation, connect the speaker leads to 25V and COM, leaving the link

16、 connected between COM and GND. For balanced operation, open the link between COM 1 and GND. If the output transformer center tap must be grounded, connect a jumper between 25VCT and GND. CONNECTING AMPLIFIERS IN SERIES CAUTION Connect only amplifiers of the same model in series; do not mix differen

17、t amplifier types. Bogen MTl25B or MT60A amplifiers may be connected in series to increase total power output where absolutely necessary to a single speaker line. Typical output connections are shown in Table 2. Note: GND straps on all except AMP I must be opened. Input connections If the amplifier

18、Hi-Z inputs are being driven directly, simply parallel the amplifier Hi-Z inputs with a phono patch cord, and connect the input line to one amplifier. When a balanced input transformer is being used, parallel the inputs at the screw terminals. Level control adjustment It is extremely important that

19、the amplifiers have the same gain and produce equal power output. This adjustment is most easily accomplished by setting both amplifier level controls to maximum and then providing an external gain control as shown in figure 2. Make sure speech filter switches are in the same position. If an externa

20、l control cannot be provided, amplifier gain must be set with the use of an external tone source, adjusting the amplifiers to produce the same output with inputs paralleled. Always keep level controls at approximately the same position even when setting up the amplifiers. CONNECTING AMPLIFIERS IN PA

21、RALLEL It is not recommended that amplifiers be connected in parallel. However, this is sometimes unavoidable. If it is necessary to connect amplifiers in this configuration, consult our Engineering Department for instructions. POWER CONNECTIONS The booster amplifier may be operated from 120VAC or 4

22、8V to 56VDC. TABLE 2- Amplifier Series Connection No. of Amplfs. 2 3 2 2 2 MT60A 18OW, 28a MTq;SB375w, 13L? MT60A 120W, 5.2a MT?25B250W, 2.5a MT60A 120W, 12051 MT?25B25OW, 58a MT125B 250W 2oa output 7ov 7ov 25v 120v 7ov Connections AMP 1 AMP 2 + OUT AMP 1 AM P 2 AMP 3 opooooyo= 70Vooyopoo 3 Z5V WIND

23、INGS IN SERIES . O U T AMP 1 AMP 2 0 0 0 0 0 “p?=, 25V + OUT AMP 1 AMP 2 ?-. 120V b OUT AMP 1 AMP 2 000 0 0 0 P 7 o v b OUT 3 RadioFans.CN Thermal breaker If the thermal breaker opens, there will be no audio output but the AC power lamp will remain on. Wait approximately five minutes for the breaker

24、 to reset. If the breaker resets and then opens again, investigate the cause of the high temperature overload. This may be due to improper connections at the output terminals or to excessive environmental heat with inadequate ventilation. The thermal breaker will open when the temperature at any one

25、 of the output transistors is excessive. Figure 3 -DC connections 120VAC source Connect the AC power cord to a 12OVAC source. Use a 3- wire receptacle with the center pin connected to earth ground. 48V-56VDC source Connect the amplifier to a DC source capable of delivering power indicated in the Tec

26、hnical Specifications table. A polarized plug is supplied with the amplifier for making DC connections. Connect DC cable to source, making certain to observe proper polarity. An isolation diode should be used in series with the DC supply as in figure 3. OPERATION VOLUME CONTROL A volume control loca

27、ted on the rear of the unit is used primarily to compensate for variations in preamplifier output levels. The VOLUME control permits the gain of the amplifier to be preset so that the preamplifier volume control may be operated near the center of its range, rather than at an extreme maximum or minim

28、um. The VOLUME control is a screwdriver adjustment which needs to be set only once for any given preamplifier input. DC POWER OPERATION When the amplifier is operated from a DC power source, the AC power switch and AC power indicator lamp will be inoperative. Turn the amplifier on and off from the p

29、ower switch on the DC power supply or by inserting and removing the DC power leads on the rear of the unit. AC OPERATION There are two overload protective devices used with AC operation, the circuit breaker and the temperature overload thermal breaker. AC circuit breaker If the circuit breaker opens

30、, the AC power lamp will go out and the amplifier will have no output. Set the AC power switch to off and momentarily depress the red button on the circuit breaker to reset it. Return the AC power switch to on. If the breaker trips again, do not attempt to reset it but have the trouble investigated

31、by a qualified technician. MAINTENANCE CA UTION There are no user-replaceable parts within the unit. Have all internal servicing done by a qualified technician. BOGEN SERVICE We are interested in your Bogen equipment for as long as you have it. If trouble ever develops, do not hesitate to ask our ad

32、vice or assistance. Information can be obtained by writing to Service Department, Bogen Division, P.O. Box 500, Paramus, N.J. 07652. When communicating with us, give the model and series designation of your unit. Describe the difficulty and include details on the electrical connections to and the ty

33、pes of associated equipment, such as preamplifier, speakers, etc. We will send you service information if the trouble appears simple. If the trouble requires servicing, we will send you the name and address of the nearest authorized Bogen service agency. Before returning any equipment to Bogen, cont

34、act the Bogen Service Department at the above address. If you do ship the unit, pack it carefully to avoid damage in transit. Send the unit fully insured and prepaid. It will be promptly repaired and returned to you freight collect. REPLACEMENT PARTS Most components used in the amplifier are standar

35、d parts available through reputable parts suppliers. The parts listed here may be obtained from Bogen distributors, service agencies or directly from the factory. When ordering a part, specify the part number and the description of the part as listed. Specify the model of the unit and give the serie

36、s designation, which is a letter followed by numbers, stamped on the chassis. For parts on circuit boards, also give the component board assembly number, which begins with “45”. When replacing transistors, use those made by the manu- facturers specified. Transistors from other suppliers may not be s

37、atisfactory. Certain resistors must be Allen-Bradley. These are designated by “AB” on the schematic diagram. Replacing transistors If a transistor must be unsoldered for testing or replacement, be certain to remove all power from the unit to prevent possible voltage transients in the circuit which m

38、ight damage the transistor. To prevent overheating the transistor when soldering or unsoldering a lead, grip the lead between the point of heat and the case with pliers or tweezers. These will act as a heat sink to conduct heat away from the transistor. Do not bend a transistor lead closer than 1 /

39、16” from the transistor case. 4 RadioFans.CN Power transistors must be properly mounted to insure good heat dissipation. Make certain there is no foreign matter on the contact surfaces between the transistor and the heat sink and brush a thin coating of heat transfer compound (such as Dow Corning No

40、. 340 Compound silicon grease) on both surfaces. Similarly coat any insulators used between the transistor and the heat sink and secure the transistor firmly to the heat sink. Schematic Ref. Part No. Description Chassis Cl01 Cl02 Cap, elect, 8800 F, 75V (MT-125B) Cap, elect, 13,000 F, 4OV (MT-125B)

41、C201 79-l 18-004 79-l 18-002 79-509-05sCapacitor, electrolytic, 6000 F, 75V (MT-6OA) C202 79- 118-006Cap, elect, 5000 F, 50V (MT-60A) CB20194-0017-09 Circuit breaker, hold, 1.65A CB102 CR101 CR202, 203 CR102 LlOl QIOI, 102 94-0017-18 94-0014-07 96-52024 1 (MT-6OA) Circuit breaker, 3.9A (MT-125B) The

42、rmal breaker, 105C Diode, HVR3 96-5241-01 96-5373-01 95-5173-01 96-5385-01 Diode, 300 piv 3A (MT-60A) Bridge rectifier, 35A (MT-125B) Coil, .5 H Transistor, 2N3055H RCA (MT-60A) or Q101-106 96-5385-01Transistor, 2N3055H RCA (MT-125B) R204 76-114-101Resistor, .1 ohm, 5W (MT-60A) R102, 103, 105, 106 R

43、104, 107 SlOl T201 TlOl T202 T102 FlOl FlOl 76-l 14-099 76-l 14-107 81-100-001 83-755-000 83-794-000 83-450-000 83-454-000 94-0005- 18 94-0005-20 Resistor, .22 ohm, 5W (MT-125B) Resistor, 3.3 ohm, 5W (MT-125B) Switch, power Transformer, power (MT-6OA) Transformer, power (MT-125B) Transformer, output

44、 (MT-6OA) Transformer, output (MT-125B) Fuse, 3A slo-blo (MT-60A) Fuse, 6A slo-blo (MT-125B) P.C. board - c2 C4 c9 Cl0 CR1-4 ;: 8 R3 R4 R8 Rll 45-7084-01 Board assembly (MT-125B) 45-7048-01Board assembly (MT-60A) 79-5 12-040Capacitor, tantalum, 6.8 F, 35V 79-008-065Cap, electrolytic, 10 F, 63V 79-00

45、8-062Cap, elect, 100 F, 50V 79-l 12-001Cap, elect, 500 F, 65V 96-5333-01Diode, 400 piv 1A 96-5321-01Transistor, MPS-6767 96-5365-o 1Transistor, MPS-A56 96-5316-01Transistor, (2N6107) 96-5327-01Transistor, (2N6292) 77-001-743Control, 200 kohm, screw-adjust 75-l 54-304Resistor, 300 kohm, 1/4W, 1% 75-154-104Resistor, 100 kohm, 1/4W, 1% 75-154-124Resistor, 120 kohm, 1/4W, 1% 76-520-680Resistor, 68 ohm, 1/2W, 5%, fire retardant R16, 1776-107-096 Resistor, .82 ohm, 2W R20 76-l 14-101Resistor, .l ohm, 5W (MT60A) Sl 8 I-003-067Switch, slide DPDT RadioFans.CN RadioFans.CN