Dynacord-DPA4245-pwr-sm维修电路原理图.pdf

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1、 SERVICE MANUALDPA 4245 / DPA 4260 POWER AMPLIFIER RadioFans.CN 收音机爱 好者资料库1MEASUREMENT SPECIFICATIONS: DPA power amplifierscomplete applianceNames of the individual printed board assemblies and their corresponding EDP numbers:EDP numbers of the main boardsDPA 4245DPA 426084 18884 189Board sectionInd

2、exMain PCB1Supply PCB4LED PCB3Input-PCB (index 1) and Output-PCB (Index 2) are located on the printed board assembly 81340.Measuring conditions, unless differently specified:- measuring tolerance:X= 1.5dB- measuring frequency:f = 1kHz- all stated levels refer to:U= 775mV (0dBu)- level controls are s

3、et to their clockwise margin:- XLR connector pin-assignment:PIN 1= GROUND/SHIELDPIN 2 = + INPUTPIN 3 = - INPUT- source impedance for the induction via the XLR-type connector: R(Q) = 50 ohms- the AMPLIFIER PCB is provided with service connectors:CNS1CNS2CNRCPINAssigned toPINAssigned toPINAssigned to1

4、-Vcc1LIM A Switch1LIM Out A2BIAS +A2-15V2LIM Out B3BIAS -A3LIM B Switch3Standby via RC4FAN Voltage4+15V4Standby LED5+Vcc5AGND5-Vss6BIAS +B6Speaker Out A6+Vss7BIAS -B7Relay/Protect7n.c.8Temp Heatsink8Speaker Out B8n.c.- Pin-assignment of the power amplifiers output connector:PINFunctionChannel1+ pole

5、 of the 100V output and + pole of the 25V output2- pole of the 25V output and + pole of the 70V output3- pole of the 70V output and - pole of the 100V outputB4+ pole Direct Output5- pole Direct Output6,7not assigned-8- pole Direct Output9+ pole Direct Output10- pole of the 70V output and - pole of t

6、he 100V outputA11- pole of the 25V output and + pole of the 70V output12+ pole of the 100V output and + pole of the 25V outputPin-assignment of the Power Remote connector:PIN 1 control voltage -PIN 2 control voltage +RadioFans.CN 收音机爱 好者资料库2Nominal load impedances100V output70V output25V outputDPA 4

7、24528,5 14 1,8 DPA 426020 9,8 1,25 1. Operation voltage: U(B) = 230V / 50Hz . 60Hz2. Deviation limit of the operation voltage:-30% . +10%3. Power consumption (both channels driven via the 100V output, f = 1kHz)DPA 4245DPA 4260idling condition power consumption30-60W40-80Wnominal power consumption (n

8、ominal load)1580W1950Wstandard power consumption (nominal load)470W620Wmaximum power consumption (nominal load)1680W2180Wpower consumption at 1/8 of the maximum output capacity600W870W4. Settings4.1. IDLING CURRENT ADJUSTMENTConnect the DC-volt meter at the BIAS measuring points (refer to service co

9、nnectors) and adjust the idlingcurrent via the trim potentiometer VR101/VR301 (located on the Main PCB). Adjust both channels of the poweramplifier A&B to U(DC) = 7.5mV. Adjusting the idling current has to be performed at normal roomtemperature. In case the power amplifier had previously been operat

10、ed, it has to be given several hours to regainits normal temperature.4.2. VCA - OFFSETRhythmically open and short-circuit CNS2.1 and CNS2.2 for channel A as well as CNS2.3 and CNS2.2 forchannel B. The switches are located on the Main PCB. Using VR100 or VR300 respectively to adjust the poweramplifie

11、rs Direct Output to its minimum offset (with oscilloscope to minimal peak value or to the audibleminimal volume of the interfering pulse).5. Functioning test5.1. OUTPUT - offset voltageDC-voltage measuring at the Direct Output A/B with U(DC) 10mV.5.2. LIMITER5.2.1. Voltage limiterBoth channels separ

12、ately driven without load via the Direct Output with a 1 kHz signal up to U(A) = 38V.Increase the input voltage by 10 dB. The LIMITER LED lights and the output voltage ascents by approx. 1.5 dBor 2.5 dB respectively to approx. 44V or 52V, respectively. The distortion rate of the limited signal shoul

13、d notascent above 0.8%.5.2.2. Distortion limiterBoth channels separately driven via the Direct Output at 2 with a 1 kHz signal up to U(A) = 20V or U(A) =25V, respectively. Increase the input voltage by 5 dB. The LIMITER LED lights and the output voltage ascentsby approx. 1.5dB to approx. 25V or 29V

14、respectively and it is slightly clipping. The distortion rate of the limitedsignal is approx. THD = 2 . 3%. Further increasing the input signal by +10dB should not result in a remarkablyhigher clipping of the output signal.35.2.3. Attack- and release timesseparately testing the power amplifier chann

15、els is mandatory: Test has to be performed at the Direct Outputwithout load.1.) Drive the power amplifiers input with a burst signal (f = 1kHz, 10 cycles, rate : 3 sec.) and U(E) = +10dBu.2.) Monitor the output signal via oscilloscope. After 1 - 2 signal periods, the limiter has reduced the majordis

16、tortion to a minor residual distortion (THD 1%)attack time: approx. 2 msrelease time: approx. 130 ms5.3 POWER-ON DELAYFeed the test signal to the power amplifier input. Switch the power amplifier ON using the Power On switch.Approximately 2 seconds after pressing the Power On switch, the signal is p

17、resent at the output.5.4 POWER REMOTESwitch the power of the appliance OFF. Feed a control voltage of +24V to the Power Remote input. The poweramplifier has to start operation and after disconnecting the control voltage has to go off again.5.5 FAN CONTROLUpon powering-on the power amplifier, the fan

18、s will run for approximately 2 seconds and stop when the poweramplifier has re-gained its normal temperature. In idling condition (power-on, no signal present) the fans areswitched between the SLOW and OFF mode, depending on the heat sinks temperature. Connecting the CNS1.8via a 5k resistor to +15V

19、lets the fans run in SLOW mode. A FAN VOLTAGE of 16.8V DC can be measuredbetween pin CNS2.4 and pin CNS1.4. When disconnecting CN5, the fans will run in FAST mode. A FANVOLTAGE of 28V DC is measured between pin CNS2.4 and pin CNS1.4.5.6 SOAR-PROTECTION TESTChannels separately driven up to 0dB via th

20、e Direct-Output, terminated with 4. Parallel connect an 1 resistor.The protection circuit reacts and tries continuously to re-start! The protect-LED lights.5.7 SHORT-CIRCUIT CURRENT-LIMITING TESTseparately testing the power amplifier channels without load is mandatory:- drive the channel with a burs

21、t signal (f = 1kHz, 1-3 cycles, rate 1 sec.), at the Direct Output withU(E) = 0dBu.- connect a load resistor of 1.- the short-circuit current-limiter limits the output voltage at the load resistor symmetrically (monitor viaoscilloscope!) to a peak voltage value of 15V or 20V respectively (approx. 15

22、A or 20A respectively maximumpeak output current).5.8 DC-voltage and HF-Protection Circuit- Testing the protection circuitry against the occurrence of DC-voltage and HF at the output is only possibledirectly via the Main PCB when it is not installed in the appliance.5.9 INDICATORS TESTFeed a 1kHz si

23、ne signal while slowly increasing the level. At approx. -30dBu the SIGNAL LEDs will light andat approx. +1.5dBu the Limit LED will light.46. Level CHANNEL A B6.1. VOLTAGE AMPLIFICATIONApplianceInputU(E)Measuring pointvUU(A)LoadFrequencyDPA 4245CH. A/B0dBuDirect Out A/B33.8dBu37.8V41kHzDPA 4245CH. A/

24、B0dBu100V Output42.2dBu99.2V28.51kHzDPA 4245CH. A/B0dBu70V Output39.3dBu71.6V141kHzDPA 4245CH. A/B0dBu25V Output30.2dBu25.1V1.8V1kHzDPA 4245CH. A0dBuBRIDGED OUT39.8dBu76V81kHzDPA 4260CH. A/B0dBuDirect Out A/B34.9dBu43V41kHzDPA 4260CH. A/B0dBu100V Output41.8dBu95.2V201kHzDPA 4260CH. A/B0dBu70V Output

25、39dBu68.8V9.81kHzDPA 4260CH. A/B0dBu25V Output29.8dBu24V1.251kHzDPA 4260CH. A0dBuBRIDGED OUT41dBu87.3V81kHz6.2. MAXIMUM INPUT LEVEL: U(E) = +21dBu7. GROUND LIFT switchThe circuit ground (at the input or the output connector) is measured versus the common ground of the enclosure(contact at the ground

26、 terminal, located on the rear panel - or common ground of the mains cord).without input transformer GROUNDED : R = 0 with input transformerGROUNDED: R = 0 NOT GROUNDED: R = 5 NOT GROUNDED: R8. Amplitude - Non-Linearities- MBW = 80kHz- all channels terminated with nominal load at nominal power, Dire

27、ct Output at 8 or at 4 respectively, atnominal powerMeasurementDPA 4245DPA 4260Remarks100V70V25VDirect100V70V25VDirectTHD+N0.1%0.2%0.3%0.05%0.1%0.2%0.3%0.05%1kHzIMD-SMPTE0.1%0.3%0.5%0.08%0.2%0.3%0.5%0.08%60Hz, 7kHzDIM 300.2%0.2%0.2%0.03%0.2%0.3%0.3%0.03%3.15kHz,15kHz9. Frequency ResponseThe frequenc

28、y response is linear. (mind the border frequencies)fU -1dBfO -1dBfU -3dBfO -3dB100V Output60Hz17kHz45Hz26kHz70V Output60Hz17kHz45Hz26kHz25V Output60Hz12kHz45Hz22kHzDirect Output60Hz22kHz45Hz30kHz10. Insert AttenuationDrive the power amplifier in idling condition via the transformer outputs up to the

29、 nominal output voltage.Connect the nominal load and measure the level changes.DPA 4245DPA 4260100V Output0,7 dB0,7 dB70V Output0,8 dB0,8 dB25V Output1,1 dB1,1 dB511. CrosstalkIt is necessary to align the output transformers when testing the crosstalk. Therefore, turn the transformer outputsby 90 to

30、 each other and both by 45 to the rear panel. Terminate the 100V-outputs with nominal load and feed a1kHz signal with -10dBu to the B-channel. Measure the crosstalk at the 100V output of the A-channel using aselective band pass filter and suitable measuring equipment. Turn the upper transformer for

31、minimal reading.Apply a 1kHz signal with -10dBu at the A-channel and measure the crosstalk at the B-channel. Crosstalkattenuation on both channels has to at least 80dB .12. Noise interference- U(F) = external voltage un-weighted with B = 22 Hz 22 kHz, effective value (IEC 268-1)- U(G) = noise voltag

32、e, frequency-weighting filter according to CCIR-468-3, quasi peak weighted (IEC 268-1)- U(A) = interference voltage A-weighted, dB(A), effective value (IEC 268-1)- Signal-to-noise ratio referenced to the maximum output voltage at nominal load, A-weighted- All inputs have to be terminated with 50 eac

33、h; during the noise interference measurement, the outputs have tobe without loadPower amplifierOutputU(F)dBuU(G)dBuU(A)dBuIN(A)dBuS/N-R.dBLEVEL control upDPA 4245, 4260100V-55-45-57-102100DPA 4245, 426070V-58-47-60-102100DPA 4245, 426025V-68-56-70-102100DPA 4245, 4260Direct-64-52-66-102100LEVEL cont

34、rol downDPA 4245, 4260100V-57-47-59-DPA 4245, 426070V-59-50-61-DPA 4245, 426025V-70-58-72-DPA 4245, 4260Direct-66-54-68-13. Settings when shippedBRIDGED MODE switch set to NORMAL.INPUT ROUTING switch set to DUAL/STEREO.LEVEL control all the way right.14. Dimensions and WeightPower amplifierWeightDim

35、ensions in mmDPA 424520.5kg483 x 132.5 x 385.5DPA 426022.5kg483 x 132.5 x 385.5Seite / Page 1 / 9Ersatzteilliste - Bill of Materials 121714DPA 4245 2X450W VERST. Pos. Nr. Ref. No.Best. Nr. Part No.BezeichnungDescriptionZubehrAccessories & packing material355871BEDIENUNGSANL. DPA4245/426user manual D

36、PA4245/4260 300425KABEL-NETZ 2.0 M 10A power cable Europe 354179KABELGEHUSE 12POL KGS-MSconnector housing 354178STECKERLEISTE 12POL IC2.5/connector male 12-pin 354885BUCHSENLEISTE 2POL connector female 2-pole 354691BUCHSENLEISTE 3POL connector female 3-pole 332652KRT. L 2400 612X570X270carton outer

37、347526KRT. IN L 2400 502X465X155carton inner 303715STYROPOR-ECK 150X150X150X50styrofoam #2 348018SCHUTZFOLIE 1200X800X0,05 poly bag 327495STYROPOR-ECK 150X150X100X50styrofoam #1 345438SCHUTZHLLE 165X345X0,05 plastic bag 349988FALTEINLAGE 750X280carton filler 349989FALTEINLAGE 1864X150carton filler M

38、echanische TeileCabinet materialG0010343270GLRI GBPC 3504 rectifier GBPC-P 3504 337059KNOPF-TASTE 12X7 SW 3.3push button black 12x7 357958DK 11 SW/WS/RT C 6FL rotary knob 348415LFTER TYP FBAO8A24H DCfan dc 24V 349693KABEL-KONFEKT 4POL 0.670Mribbon cable assy 4-way 346790KABEL-KONFEKT 8POL 0.300Mribb

39、on cable assy 8way 349691KABEL-KONFEKT 8POL 0.440Mribbon cable assy 8way 355873FB.DPA4245 BEDfront panel DPA4245 355915DEC.3HE DPA4245,4260 top cover 354549NT-RG.Q44/S900/CPS1 230V power transformer 230V 348805WI-SO PTC K155 100GRADsafety component PTC 348341FEDERLEISTE 3POL CE100-connector female 3

40、-pole 354805T-RG.DPA4245 100Voutput transformer 100V 348341FEDERLEISTE 3POL CE100-connector female 3-pole 841888PCBAR#DPA4245 pcb assy 84188 CNAC1343516FL.STECKER 4.8/0.5 connector 4.8mm faston CNAC2343516FL.STECKER 4.8/0.5 connector 4.8mm faston CNGND343516FL.STECKER 4.8/0.5 connector 4.8mm faston

41、CNGN1330269FL.STECKER 6.3/0.8 connector 6.3mm faston CN001344862MESSERLST. 8POL connector male 8-pin CN002348334STIFTLEISTE 3POL MLSSconnector male 3-pin CN003348334STIFTLEISTE 3POL MLSSconnector male 3-pin CN005348334STIFTLEISTE 3POL MLSSconnector male 3-pin CN007330269FL.STECKER 6.3/0.8 connector

42、6.3mm faston CN010330269FL.STECKER 6.3/0.8 connector 6.3mm faston CN013330269FL.STECKER 6.3/0.8 connector 6.3mm faston CN018341937MESSERLST. 4POL connector male 4-pin CN019330269FL.STECKER 6.3/0.8 connector 6.3mm faston Seite / Page 2 / 9 121714DPA 4245 2X450W VERST. Pos. Nr. Ref. No.Best. Nr. Part

43、No.BezeichnungDescriptionCN020344862MESSERLST. 8POL connector male 8-pin CN08X343516FL.STECKER 4.8/0.5 connector 4.8mm faston CN18X341937MESSERLST. 4POL connector male 4-pin CN20X344862MESSERLST. 8POL connector male 8-pin C0001342923KO-FOL 0.220MF 63V 5%cap mylar 220nF C0002307445KO-EL 10.000MF 35V

44、cap electrolytic 10uF/35V C0005329021KO-KER 0.10MF 100V 20%cap ceramic 100nF C0006329021KO-KER 0.10MF 100V 20%cap ceramic 100nF C0007343530KO-EL 47.000MF 50V cap electrolytic 47uF/50V C0008329021KO-KER 0.10MF 100V 20%cap ceramic 100nF C0011351835KO-EL 4700.000MF 100V 20%cap electrolytic 4700uF/100C0

45、012351835KO-EL 4700.000MF 100V 20%cap electrolytic 4700uF/100C0013351835KO-EL 4700.000MF 100V 20%cap electrolytic 4700uF/100C0014351835KO-EL 4700.000MF 100V 20%cap electrolytic 4700uF/100C0015341714KO-SO 0.10MF 275V 20% Ksafety cap 100nF/275V C0016329021KO-KER 0.10MF 100V 20%cap ceramic 100nF C00173

46、29021KO-KER 0.10MF 100V 20%cap ceramic 100nF C0018327366KO-EL 4.700MF 50V BIPcap bip electr. 4.7uF/50V C0019329021KO-KER 0.10MF 100V 20%cap ceramic 100nF C0022329021KO-KER 0.10MF 100V 20%cap ceramic 100nF C0023329021KO-KER 0.10MF 100V 20%cap ceramic 100nF C0024335935KO-EL 2200.000MF 35V cap electrol

47、ytic 2200uF/35VC0025335935KO-EL 2200.000MF 35V cap electrolytic 2200uF/35VC0026343530KO-EL 47.000MF 50V cap electrolytic 47uF/50V C0027343530KO-EL 47.000MF 50V cap electrolytic 47uF/50V C0028301524KO-KER 47.0PF 500V 10%cap ceramic 47pF C0029301524KO-KER 47.0PF 500V 10%cap ceramic 47pF C0030329021KO-

48、KER 0.10MF 100V 20%cap ceramic 100nF C0031329021KO-KER 0.10MF 100V 20%cap ceramic 100nF C0032341714KO-SO 0.10MF 275V 20% Ksafety cap 100nF/275V C0100301558KO-KER 33.0PF 100V 2%cap ceramic 33pF C0101301558KO-KER 33.0PF 100V 2%cap ceramic 33pF C0102301478KO-EL 22.000MF 63V cap electrolytic 22uF/63V C0

49、103335787KO-KER 15.0PF 100V 2%cap ceramic 15pF C0104335787KO-KER 15.0PF 100V 2%cap ceramic 15pF C0105301458KO-EL 2.200MF 63V cap electrolytic 2.2uF/63V C0106327390KO-FOL 470.000PF 100V 5%cap mylar 470pF C0107340988KO-FOL 0.470MF 63V 5%cap mylar 470nF C0108301530KO-KER 100.0PF 500V 10%cap ceramic 100

50、pF C0109343532KO-EL 100.000MF 25V cap electrolytic 100uF/25V C0110343532KO-EL 100.000MF 25V cap electrolytic 100uF/25V C0111340988KO-FOL 0.470MF 63V 5%cap mylar 470nF C0112343532KO-EL 100.000MF 25V cap electrolytic 100uF/25V C0113343532KO-EL 100.000MF 25V cap electrolytic 100uF/25V C0114329021KO-KER