Bogen-MT125A-pa-sm维修电路原理图.pdf

6OGENca? Solid-State PA ComponentsINSTALLATION TABLE I. COMPANION UNITS AND ACCESSORIESUNPACKINGThe amplifier was thoroughly checked before leaving thefactory. Inspect the amplifier and shipping containercarefully for evidence of improper handling during ship-ment. In case of damage, make an immediate claim to thedealer or distributor from whom the unit was purchased. Ifthe amplifier was shipped to you, notify the carrier withoutdelay and file a claim.ModelCAMCMCHS-MCTMMX6A-5RPK-I 8DescriptionFive input solid-state preamplifier mixer.Five input solid-state preamplifier mixer.Seven input solid-state preamplifier mixer.Seven input solid-state preamplifier mixer.Six input solid-state preamplifier mixer.Rack mounting kit 19” x 7” (mounts 2units).INPUT CONNECTIONSKeep the input lead away from the output lead and acpower cables. Unless the driving source provides alow-impedance output, keep the input lead under ten feetTL600 Low-impedance (500/6OOs1) plug-intransformer.TL10K Bridging (1 Oka) plug-in transformer.MODELS MT60& MT125A60-Watt and 125-WattBooster AmplifiersIIMT60IMT125AIIIIiPOWER OUTPUT:PEAK OUTPUT:E:tiULAlIUN :PUT SENSITIVITY (FOR60 watts 125 watts120 watts 250 watts 2 dB, 30 Hz to 20k Hz 2 dB, 40 Hz to 20k HzLess than 2% at rated output Less than 2% at rated output-80 dB below rated output -80 dB below rated outputLess than 2 dB variation from no load to full load.RATED OUTPUT): Hi Z 0.2V; Lo Z balanced with TL600 xfmr, .045V; Hi Z with TL 10k xfmr, 0.lV.INPUT IMPEDANCE: Hi Z 50k; Lo Z 500/60052 with TL600 xfmr; Bridging l O k with TL 10k xfmr.OUTPUT CONNECTIONS:8R: 25VCT, 25V, 16fi, 70V terminals8R, 25VCT, 25V, 16a, 70V terminalsOUTPUT IMPEDANCE 25VCT; 10.4s2 (25V); 8R; 16R; 25VCT; 5s2 (25V); 8R, 16R; 40R(BALANCED OR UNBALANCED):83SJ (70V)(7OV)CONTROLS AND INDICATORS: AC power switch, ac power indicator lamp, volume control, music-speech selectorSEMICONDUCTORS:POWER CONSUMPTION:s w i t c h .6 silicon transistors; 7 diodes 8 silicon transistors; 7 diodes120VAC 60HZ. 168 watts Ratedoutput120VAC 60HZ, 300 watts Rated120VAC 60HZ, 22wattsoutput Quiescent 120VAC 60HZ, 30 watts Quiescent(No Output) (No Output)48-56 VDC, 1 Amp 30 watts 48-56 VDC, 2.25 Amps 62.5 wattsoutput48-56 VDC, 15 mA Quiescent (No48-56 VDC, 15 mA Quiescent (NoAUXPOWERRECEPTACLE:OVERLOAD PROTECTION:Output)550 wattsAC circuit breaker. 1 .65A Hold: DCOutput)390 wattsAC circuit breaker. 2.5A Hold; DCDIMENSIONS:WEIGHT:circuit breaker. I .65A Hold; Thermal circuit breaker, 2.5A Hold; Thermalbreaker, 95 C. with recovery in breaker, 104” C. with recovery inIapproximately 2 minutes.8” W. x 13” D. x 6” H.18 Ibs.approximately 2 minutes.8” W. x 13” D. x 6” H.25 Ibs.*Variations in performance characteristics normally will not exceed I dB.PRINTED IN U.S.A.3-75PMP #1390LEAR SIEGLER, INC. 54-5521-01RadioFans.CN 收音机爱 好者资料库in length. Refer to Table I for Bogen preamplifiers suitablefor use with the amplifier.HIGH IMPEDANCE INPUT: The amplifier can be driven tofull output from any source developing 200 mV across oneof the Hi-Z inputs. Wire a single-conductor, low-capacityshielded input cable to a standard phono plug (Cinch 18A,or equivalent) and connect to one of the Hi-Z jacks on therear of the chassis.LOW IMPEDANCE INPUT: The amplifier may be drivenfrom a low-impedance (500/6OOa) input, if a Bogen ModelTL-600 transformer is installed in socket X1 on top of thechassis. Connect a twisted, shielded pair (Bogen BB-8450,or equiv.) input cable to the BAL. INPUT LOW Z terminalstrip on the rear of the unit. Use the two terminals on theright of the strip and connect the cable shield to the GNDterminal on the left. If an unbalanced input is required,connect a jumper from the GND terminal to the adjacentinput terminal.CAUTIONRemove all power from unit before installingtransformers.BRIDGING INPUT: The inputs for two or more amplifiersmay be paralleled without loss of gain. To do this, install aBogen Model TL-IOK transformer in socket X1 on top ofthe chassis. Connect the bridged inputs to BAL LOW Zterminal strip on the rear of the unit. Use the two terminalson the right of the strip and connect the cable shields to theGND terminal on the left. If an unbalanced input isrequired, connect a jumper from the GND terminal to theadjacent input terminal.CONSTANT-VOLTAGE INPUT: The amplifier can bedriven from a standard public address amplifier thatprovides a 25volt or 70-volt constant voltage output. To dothis, connect the output of the amplifier to one of the Hi-ZINPUT jacks via a resistor network (see figure 1). Theresistors shown in figure 1 are in addition to the normalloudspeaker load on the output of the public addressamplifier.-OUTPUTTERMINALSTRIP OFDRIVERAMPLIFIERPOWERAMPLIFIER74-0730-AAT 70V RI . 10K, WA T 25V RI - 3.3K, WFigure 1 - Connection to Constant - VoltageP.A. Amplifier Driver.OUTPUT CONNECTIONSSpeakers may be connected with standard flexible linecord (zip-cord) and up to 100 feet of cable may be usedwithout appreciable loss. Class II wiring is acceptable unlessprohibited by local codes.70V CONSTANT-VOLTAGE OUTPUT. For 70V constant-voltage operation, connect the speaker leads to the 70Vand COM 2 terminals on the rear of unit. If ground-ing is required, connect a jumper from the COM 2 to GND.25V CONSTANT-VOLTAGE OUTPUT. For 25V constant-voltage unbalanced operation, connect the speaker leads to25V and COM 1, leaving the link connected betweenCOM 1 and GND. For balanced operation, open the linkbetween COM 1 and GND. If the output transformer centertap must be grounded, connect a jumper between 25VCTand GND.16 OHM & 8 OHM OUTPUT. For 16fi or 8R operation,connect the speaker leads between the desired outputterminal and COM 1. If ungrounded operation is desired,open the link between COM 1 and GND.CONNECTING AMPLIFIERS IN SERIESPairs of Bogen MT1 25A amplifiers or MT60 amplifierscan be connected in series to effectively double the poweroutput into the same loadline. See Figure 2 for connectiondiagrams. Be certain to remove the link between COM 1 andGND of amplifier No. 2.Depending on the impedance of the signal source, applythe input signal to the HI Z or LO Z input of amplifier No.1. Use jumpers to connect the appropriate input ofa_ amplifier No. 2 in parallel with that of amplifier No. 1.It is necessary that both amplifier volume controls be atthe same setting to assure that each amplifier will share theload equally.AMPLIFIER IGND COM116f-lAMPLIFIER 2GND COM1l6n FOR MT60en 8R FOR MT125AMPLIFIER I AMPLIFIER 2874-1017-01GND COM1 25VCT GND COM1 25VCTL_1IL*25VMT60 AND MT125AbFigure 2 - Connecting Amplifiers in SeriesGND COM I 16fl COM2 7ov120VA74-2018-01125WFigure 3 - MT1 25A Connections for 120-Volt OperationRadioFans.CN 收音机爱 好者资料库CONNECTIONS FOR 120-VOLT OUTPUT(MT125A ONLY)Figure 3 shows connections for 120-volt output atselected frequencies for laboratory or industrialapplications.POWER CONNECTIONS.The booster amplifier may be operated from 120 vac or48V to 56V dc.120 VAC SOURCE. Connect the ac power cord to a 120vac. source. Use a 3-wire receptacle with the center pinconnected to earth ground.If desired, auxiliary equipment may be connected to theAUX POWER receptacle on top of the unit. Do not exceedpower ratings on the schematic diagram.48V - 56V DC SOURCE. Connect the amplifier to a dcsource capable of delivering power indicated in the Techni-cal Specifications table. A two-prong polarized plug (BogenPart No. 85-0109-01; Cinch Jones No. P-302-CCT) issupplied with the amplifier for making dc connections.Connect dc cable to source making certain to observeproper polarity.VOLUME CONTROLA volume control located on the rear of the unit is usedprimarily to compensate for variations in preamplifieroutput levels. The VOLUME control permits the gain of theamplifier to be preset so that the preamplifier volumecontrol may be operated near the center of its range, ratherthan at an extreme maximum or minimum. The VOLUMEcontrol is a screwdriver adjustment which needs to be setonly once for any given preamplifier input.DC POWER OPERATIONWhen the amplifier is operated from a dc power source,the ac power switch and ac power indicator lamp will beinoperative and there will be no power at the AUX POWERreceptacle on top of the chassis. Turn the amplifier on andoff from the power switch on the dc power supply or byinserting and removing the dc power leads on the rear ofthe unit.M A I N T E N A N C EAC OPERATIONThere are two overload protective devices used with acoperation, the circuit breaker and the temperature overloadthermal breaker.AC CIRCUIT BREAKER. If the circuit breaker opens, theac power lamp will go out and the amplifier will have nooutput, but there will be power at the AUX POWERreceptacle on top of the unit. Set the ac power switch tooff and momentarily depress the red button on the circuitbreaker to reset it. Return the ac power switch to on. If thebreaker trips again, do not attempt to reset it but have thetrouble investigated by a qualified technician.THERMAL BREAKER. If the temperature thermal breakeropens, there will be no audio output but the acpower lamp will remain on. Wait approximately twominutes for the breaker to reset. If the breaker resets andthen opens again, investigate the cause of the temperatureoverload. This may be due to improper connections at theoutput terminals or to excessive environmental heat withinadequate ventillation. The thermal breaker will openwhen the temperature at any one of the output transistorsis excessive.DC OPERATIONThere are two overload protective devices used with dcoperation, the circuit breaker and the temperature overloadthermal breaker. If either device opens, there will be noaudio output. The ac power lamp does not light during dcoperation.THERMAL BREAKER, See the applicable paragraph under“AC OPERATION”.REPLACING TRANSISTORSTransistors show little, if any, deterioration with age andare considerably more reliable than the best vacuum tubes.This is why some transistors are soldered into equipmentlike resistors or capacitors. If the unit is inoperative, itgenerally is safe to assume that the transistors have notfailed and that the trouble is elsewhere in the equipment.If a transistor must be unsoldered for testing orreplacement, be certain to remove all power from the unitto prevent possible voltage transients in the circuit whichmight damage the transistor. To prevent overheating thetransistor when soldering or unsoldering a lead, grip thelead between the point of heat and the case with pliers ortweezers. These will act as a heat sink to conduct heat awayfrom the transistor. Do not bend a transistor lead closerthan 1/ 16” from the transistor case.Power transistors must be properly mounted to insuregood heat dissipation. Make certain there is no foreignmatter on the contact surfaces between the transistor andthe heat sink and brush a thin coating of heat transfercompound (such as Dow Corning No. 340 Compoundsilicon grease or equivalent) on both surfaces. Similarly coatany insulators used between the transistor and the heat sinkand secure the transistor firmly to the heat sink.BOGEN SERVICEWe are interested in your Bogen equipment for as long asyou have it. If trouble ever develops, do not hesitate to askour advice or assistance. Information can be obtained bywriting to Service Department, Bogen Division, P.O. BOX500, Paramus, N.J. 07652.When communicating with us, give the model and seriesdesignation of your unit. Describe the difficulty andinclude details on the electrical connections to and thetypes of associated equipment, such as preamplifier,speakers, etc. We will send you service information if thetrouble appears simple. If the trouble requires servicing, we-3-will send you the name and address of the nearestauthorized Bogen service agency.Do not return the unit to Bogen without prior clearancefrom our Service Department. If you do ship the unit, packit carefully to avoid damage in transit. Send the unit, fullyinsured and prepaid, via United Parcel or Railway Express.Do not ship via parcel post unless so instructed.REPLACEMENT PARTSMost components used in the amplifier are standardparts available through reputable parts jobbers. The partslisted here may be obtained from Bogen distributors,Ref. No. Part No.Alc2C5C9,llCl0CR1,3,4,5CR2QlQ2R17,19R18,2045-9933-01 (MT60)45-9938-01 (MT1 25A)94-5067-01Printed Circuit Board79-008-06379-008-06279-112-002 (MT1 25A)79-l 12-007 (MT60)96-5333-0196-5202-0196-5321-01MPS-6767 (Motorola)96-5342-01MJE 172 (Motorola)45-9866-0145-9865-0176-107-10576-l 16-003service agencies or directly from the factory. When orderinga part, specify a part number and description of the part aslisted. Specify the model of the unit and give the seriesdesignation,which is a letter followed by numbers,screened on the chassis. For parts on circuit boards, alsogive the component board assembly number, which beginswith “45”.When replacing transistors, use those made by thespecified manufacturers. Transistors from other suppliersmay not be satisfactory. Certain resistors must be Allen-Bradley. These are designated by “AB” on the schematicdiagram.Ref. No. Part No.CHASSIS ELECTRICAL PARTSCl04 79-509-054 (MT60)79-509-075 (MT1 25A)Cl05 79-009-07 1CBlOl, 102 94-0017-15 (MT125A)CB103 94-00 14-03CR 101,102,103 96-5241-01 (MT60)96-5355-01 (MT125A)1101 94-0302-04QlOl, 103 96-5351-012N6254 (RCA) (MT60)96-53%01 (MT60)QlOl-104 96-5315-01 (MT125A)RlOl 77-001-372SW1 81-003-059SW102 8 l-002-098TlOl 83-776-000 (MT60)83-766-000 (MT1 25A)T102 83-427-O 10 (MT60)83-425-000 (MT1 25A),- OWNERS WARRANTY 1Bogen solid state sound and intercom equipment is guaranteed against defects in material andworkmanship for one year from the date of sale to the original purchaser, provided that theequipment has not been subjected to abuse or accident or altered in any way. Any part of theequipment covered by this warranty which, with normal installation and use, becomes defectivewill be repaired or replaced by Bogen, provided the equipment IS delivered or shipped prepaid andinsured to our authorized service station or to the Bogen Factory Service Department, Route 4 andForest Avenue, Paramus, New Jersey 07652. The equipment may be picked up by you personallyor will be returned to you freight prepaid.Models containing vacuum tubes carry the same warranty as above, except that it does notapply to the vacuum tubes, which are guaranteed for 90 days.The registration card enclosed with the equipment must be completed and mailed within fivedays of purchase to place the warranty in effect.-4-