CARVER P R OFE S SIO N AL PM 2.0t SERVICE MANUAL � � C�����R � CJON .-.q ���ti ��������H������H 'llKR ·-· !Powerf!aJJ ff...
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With a working knowledge of what makes it "tick" the PM 2.0t is actually quite tame. Almost any problem encountered can be resolved with the low voltage tests outlined in this manual.
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PM 2.0t WARNING WHEN SERVICING THE POWER SUPPLY PRIMARY CIRCUIT AN ISOLATION TRANSFORMER MUST BE USED ·· A SERIOUS SHOCK HAZARD AND POSSIBLE DAMAGE TO EQUIPMENT EXISTS IF THIS PRECAUTION IS NOT FOLLOWED When the power switch SW-1 is closed, capacitors C4 CS are charged to 160 Vdc and C6 begins to charge thru &...
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CIRCUIT REFINEMENTS Because of transistor storage, rise and fall times the switchers do not turn on and off at the exact same time as the drive signals from the regulator IC. the turn off times are not fast enough, the main switchers could go into simultaneous conduction at full duty cycle or during the start sequence, greatly exceeding their current ratings due to the very high current rise time.
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· can be accomplished only by changing the entire power supply module. PM 2.0t AMPLIFIER CIRCUIT The power amplifier section of the 2.0t is very similar to the PM 1.5 series. The primary differences in the PM2.0t are input muting, the addition of a fourth power supply rail, the power supply shut down circuitry and...
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"replace the bad part and turn the variac up" repair methods are used. It is strongly recommended that this method of troubleshooting be used when performing any repairs on the control circuitry of the PM 2.0t. CAUTION THE PM 2.0t MUST NOT BE CONNECTED TO...
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2) Set the external supply to "zero" output and connect the negative lead to the ground side of R61 (use the tubular terminal next to R6 1) and the positive lead to the cathode of D 19 or D21. 3] Turn the PM 2.0t power switch on. 4) Set the output of the external supply to 8 volts and check: a) Oscillator ramp output of Ul-7 �...
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With the power switch off, bring the Variac up to 120 Vac. There should be no current draw and the power LED should glow dimly. Reduce the line voltage to 95 Vac and turn the PM 2.0t ON. The power LED should glow brightly and the � supply itself should start within 15 seconds.
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For the remaining tests, replace the 1 amp AGC fuse with a 10 amp slow blow MDL type fuse. .m.u.st With the amplifier set for an output of 10 volts RMS, short the output of either channel. The power supply shut down and restart when the short is removed.
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10-50pF. AN INSULATED SCREW DRIVER MUST BE USED FOR THIS ADJUSTMENT! Refer to Figure 1 on page 10 for the location of C32. After this adjustment is completed, cover the access hole with a new paper "dot". PM 2.0t FREQUENCY RESPONSE Adjust the amplifier gain controls for volts at 2Khz.
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HIGH POT TEST Set the Hi-Pot to 1200 volts and turn the PM 2.0t power switch on. With one probe on the chassis, make contact with each of the line cord blades with the other probe. The unit must not fail. If a Hi-Pot failure ocures t h e u ni t ca nn ot corrected.
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PM 2.0t DISTORTION ANALYZER Sound Technology 1100B or equivalent OSCILLOSCPOE MHz dual trace VOLT/OHMETER Fluke 8010/8012 or equivalent LOW VOLTAGE POWER SUPPLY Variable from 0 to 35 Volts out at 500 mA AUTOTRANSFORMER 25 Amp 0 to 140 Volts output...
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9 I 0 L DISPLAY BLUE YELLOW R DI SPLAY ORANGE l CLIP LED R CLIP LED BLACK VOLTS SECONDARY VOLTS DISPLAYS ORANGE READY LED YELLOW XFMR GROLND • BLUE BOARD BOARD • CARVER CORPORATION NOTE 1 2.0t PRIMARY CIRCUIT BOARD WIRING SHEET SEPT THIS CIRCUIT...
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BASE D R CURRENT CONTROL CLAMP SENSE CONTROL LOW CURRENT START ��TG� ��t� OUTPUT SHUTDOWN FEED F\./D OVER CUR OVER CUR TRIP HOLDOFF CARVER CORPORATION CURRENT FEEDBACK LINE PM 2.0t BLOCK DIAGRAM POWER SUPPLY PRIMARY BOARD SHEET of I SEPT 1989...
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NOTES: UNLESS OTHERWISE SPECIF I ED RESISTANCE IN OHMS 2 CAPACITANCE IS IN uF 3 DASHED LINE INDICATES CHASSIS MTO PARTS 4 DlODES ARE 1N4148 5 R20.R25.R40 l R41 TEMP COEFFICIENT ·o· •5V FIXED TRIM CAP AS REO'O Source FOR TRANSFORMER LOT TRANSFORMER WIRE COLORS...
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·!· :"':· ·· . . ND\ES: UNLE'>� OH-\ERW\SE SPEl\f\EtJ , .. I� /4 W. •. \N 0\-\MS C.. A 'fti.(_ \\ ANCE_ \� REVISIONS 3. UZ. A. LM 3� • ..q. LINE ( ) �'-'O\NS BREP>-K BEIWEEN DA".>HED i· -� � SEE Eco's 703, 719, 738 �...
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� SPE Uf\ED ND1£S UNLE<)� 0\HE.�W\SE \N 0\-\MS Rf VISION$ Z. C.. A. l"A.C.\\ t>.NL."E. \<:, OlSOll P TtOI'< lON! l TR 3. U2. LM 3�. "'1. DA')HED LINE ( 'S:.\-\0\NS BRE.C.. K 'BEIWEEN - - - - MDUN'"TED C.. O t../\ PO NENI<;, .
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NOTE�'. U NLE5'5 01HERWISE SPEClt\E'D. IN<;IA\... L IUE.l.JLAR W 1 ¥:t 1£.RM\Np..\_ ") 'PC>INiS z; , sS', IS , 1,2,3�,S,(.., , 1,a 5. .. z!>,•55,•&J,•IZS, S" ,, uSE 1\-\(RMAL CDMPOL) � D BO\� Dt=- MICA INSULt>.10'0<5. • (I.> 'S>IDE':> IN'SiN..L. .5"'51.. EE VlNG DN i!.llS 1':131, R!:ZS K�31.
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U N L E SS OTH E R W ISE SPEC I F I E D . NOT E s : C H�':l'SI S GROU M D RE'Sl':iTO R.S. O HM� , 1 /4 l"EK M l l\l AL. AL L R\ 2.
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D l� PLAY OFFSE\ . . . ' . . • AM P ( F ROM R f VI SIO N S 5 � � C I RW I T S\-\U\ 'i:X)W N AM P ZONf L T R Dt: SC R I PT I C>f< €...
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�(�SION� __ __ · · R IO RE.At)Y 4' _, 1. 5 � LE O D I S D C. �R � Mu� I N4 14Q - l 3'V - 1 3 \I � <i � I R \ l �...
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Ut.al.f\_ RE\llS IOt-JS NOTE"): �Pf.tlf'lll>. Z!Mf L T ll: D£SC.RIV1' I ON IN�TALL H E� tJUT IH "T �� W lT H POI A-CS. SHO\NN. e.so· (RE F) ITEM � : m�EJB �� wf•EJ �� � § ZS t · OOO 'M · O !i R£.�1�TOR \ 0 �...
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Fig 1 Base drive wave form of clamping transistor 0 1 . 200 µSec / div 2 Volts / div 01 Base drive & 05 base drive Fig 2 Base drive of 04 / 05 at idle. 200 µSec / div 1 Volt / div 01 - 04/05 timing relationship Fig 3...
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Fig 4 Oscillator ramp output (CA3524) . This frequency is twice that of the switching transistors. The time period at pin 480-500 µSec. 100 µSec / div 1 Volt / div Oscillator ramp Shut down drive Fig 5 Output of U2-C pin 14 during start up or continuous over current fault condition.
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Fig 7 Collector wave form of 06 / 07 at idle with the amplifier output at zero. The idle time period should be set to 60-80 µSec. NOTE: The peak voltage swing at this point is nearly 400 volts. Caution must be used when checking 06 and 07 ! An isolation transformer must be used when servicing the primary circuitry ! !
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PM 2.0t POWER OUTPUT: 465 Watts per channel 20-20kHz both channels driven with no more than 0.5% THO into 8 Ohms. 600 Watts per channel 20-20kHz both channels driven with no more than 1.0% THO into 4 Ohms. 450 Watts per channel 20-20kHz both channels driven into 2 Ohms.
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APPENDIX A PRIMARY BOARD CIRCUIT CHANGES Starting with serial number PS-1006 several value changes were made to improve performance and reliability under adverse conditions. These changes are listed below and a re intended for ref erance only. For information concerning the updating of older units contact Carver Service. Description Changed to Carver...
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APPENDIX B EUROPEAN PRIMARY BOARD CHANGES ( 120V version) Changed to Carver P/N 24K 1/2 W 68K 1 /2 W 251-00042-00 200 2 W 820 2 W 256-20055-00 7.SK 5 W 234-00034-00 15K lO W HOK 1 /4 W 300K 1/4 W 2S1 -00 129-00 HOK 1 /4 W 300K 1/4 W...
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CONVERSION TO MONO To convert the PM 2.0t to parallel mono operation all that is required are jumper changes as shown below. With the 2.0t in the mono mode it is possible to drive low impedance loads to full rated power.
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PARTS LIST The part lists below are grouped by subassembly and contain only those items which would be difficult to obtain at a local jobber. For pricing and information on parts not listed contact Carver Service. AMPLIFIER BOARD Reference designator Description Carver P/N 01,0110,03 10,0 104,030 4...
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PM 2.0t parts list continued Reference designator Description Carver P/N Q t y U 1,U2 TL0-72 330-30001-00 J l,J4 PC Mt TRS Jack 109-20001-00 J2,J3 PC Mt XLR Jack 109-00002-00 PRIMARY BOARD Reference designator Description Carver P/N Q t y...
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PM 2.0t parts l ist continued Reference designator Description Carver P/N Q ty MPS8097 321-40000-00 02,03, 2N4123 321-40010-00 04, 05, 0 6 2N4125 32 1 -40009-00 MPS8093 32 1 -40003-00 D8,D9,D10,D11 MR82i 320-200 1 5-03 D7,D8 MR504 320-20005-03 C 13,C 1 4 lOOOµF 1 60V...
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This page left blank for notes and test procedure changes. page 36...
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