General_Music_LEM_P500_Service_Manual电路图.pdf

1 1 1 1 1 J J J J J CODE : 277319 Index one positive and one negative low rail (+/-Vcc1) and one positive and one negative high rail (+/-Vcc2). Visual CheckVisual CheckVisual CheckVisual CheckVisual Check Use compressed air to clear dust in the amplifier chassis. Before proceed to supply the amplifier check visually the internal assem- bly, if appears an evident damage find the most possible reasons that cause it. Check the wiring cables for possible interruptions or shorts. If the damage has burnt a printed circuit board dont try to repair it, re- place with a new one. Test InstrumentsTest InstrumentsTest InstrumentsTest InstrumentsTest Instruments Audio Generator Dual Trace Oscilloscope Digital Multimeter 2 1000W, 4 500W, 100 20W resistors Variac (0250Vac) Temperature Meter SetupSetupSetupSetupSetup Connect the Variac between the mains and the amplifier and set it at zero voltage. Set the amplifier in STEREO MODE and turn full clockwise the LEVEL potentiometers. Connect the audio generator to the channel inputs and set it to 1KHz 775mVRMS (0dB) sinusoidal signal. Insert the temperature meter through the IC3 interstice located at centre of heatsink. The procedures that follow must be executed subsequently in the order specified. Supply CheckSupply CheckSupply CheckSupply CheckSupply Check Remove the transformer secondary fuses (located on SUPPLY they must be 14.8 0.5Vdc. SIGNAL/CLIP SENSOR CHECK:SIGNAL/CLIP SENSOR CHECK:SIGNAL/CLIP SENSOR CHECK:SIGNAL/CLIP SENSOR CHECK:SIGNAL/CLIP SENSOR CHECK: Set the LEVEL pot to minimum, set the scope timebase at 1V/div. 200S/ div., then increase the level and check the SIGNAL/CLIP led activity: it must turn on (green light) when the amplifier output is higher than 1Vp. Set the scope at 20V/div. and increase the level, check the led: it must change from green to red colour at the amplifier output signal clipping. CURRENT AND SHORT CIRCUIT SENSOR CHECK:CURRENT AND SHORT CIRCUIT SENSOR CHECK:CURRENT AND SHORT CIRCUIT SENSOR CHECK:CURRENT AND SHORT CIRCUIT SENSOR CHECK:CURRENT AND SHORT CIRCUIT SENSOR CHECK: Set the CH2 sensitivity to 0.5V/div., connect the scope CH1, GND clip at CN3 pin 2 (AMP output) and the probe tip at TR26 (PNP) emitter, con- nect the CH2 probe tip at TR17 (NPN) emitter. Set the generator to have approx. 1Vp on the emitters: their difference must be less than 0.2V on the peaks (see Fig.3 Trace A the fan must run at maximum speed). Remove the connection, wait until the leds turn off and after some sec- onds repeat the check with -15Vdc (available on CN1 pin 4), the led PROTECT must turn on again. SOA ADJUSTMENT:SOA ADJUSTMENT:SOA ADJUSTMENT:SOA ADJUSTMENT:SOA ADJUSTMENT: Set the scope sensitivity at 5V/div. (both channels). Disconnect the fan and cut the pins A-B of J16. Connect the 4 500W load and connect the CH2 probe tip at TR23 collector, check the waveform as shown in Fig 5 Trace B, Trace A show CH1 that is also connected at TR26 (PNP) emitter. Set the scope CH2 sensitivity at 2V/div. and connect the probe tip at the testpoint TP3. Set the load at 2, wait until the temperature reaches 80C; then change the load back to 4. Adjust the generator level to have the CH1 waveshape as shown in Fig 6 Trace A. Turn the R47 trimmer to level the peaks of the CH2 waveshape as shown Fig 6 Trace b. Solder the pins A-B of J16: the CH2 trace becomes continuous. Increase the generator level for the max. displacement of the CH2 trace toward the centre of the screen Fig 7 Trace b. Wait until the temperature reaches 88C, then turn clockwise the R62 trimmer to activate the SOA control (that is displayed by CH1 trace when its peak voltage decrease Fig 7 Trace A), after some seconds, the chan- nel goes in PROTECT mode. Set the CH2 sensitivity at 5V/div. then, with its tip, check the voltage on D19 cathode: it must be 14V or more. Activate the fan and check its supply voltage: it must be 20V or more (max. speed). Fig. 2Fig. 2Fig. 2Fig. 2Fig. 2 Fig. 3Fig. 3Fig. 3Fig. 3Fig. 3 Trace A (0.5V/div.) Trace B (0.5V/div.) Fig. 5Fig. 5Fig. 5Fig. 5Fig. 5 Trace A (5V/div.) Trace B (5V/div.) Fig. 4Fig. 4Fig. 4Fig. 4Fig. 4 Trace A (0.5V/div.) Trace B (0.5V/div.) BIAS ADJUSTMENT:BIAS ADJUSTMENT:BIAS ADJUSTMENT:BIAS ADJUSTMENT:BIAS ADJUSTMENT: Remove the CH2 probe, connect CH1 GND clip to CN3 pin 1 (GND terminal) and its probe tip to CN3 pin 2 (AMP output) and set its sensitiv- ity at 1V/div. Set the generator level at zero, connect the Multimeter across the emit- ters of TR17 and TR26, when the heatsink temperature reaches 55C, turn off the cooling fan and adjust R55 trimmer to read 60.5mV. Adjust the generator level until the sinewave appears at full screen ampli- tude, No crossover distortion must be detectable: if necessary re-adjust R55. Re-connect the fan. BANDWIDTH CHECK:BANDWIDTH CHECK:BANDWIDTH CHECK:BANDWIDTH CHECK:BANDWIDTH CHECK: Sweep the generator frequency from 20Hz to 20KHz, the output level must have not detectable level changes. SLEW RATE CHECK:SLEW RATE CHECK:SLEW RATE CHECK:SLEW RATE CHECK:SLEW RATE CHECK: Set the scope sensitivity to 10V/div. 1S/div. and set the generator to 1KHz square wave mode. Check the output square wave rising and falling edge slopes: both must be 10V/S or more as shown in Fig 8. Inputs Board CheckInputs Board CheckInputs Board CheckInputs Board CheckInputs Board Check These procedures are intended for one channel at a time, repeat these operations for the other channel. SETUP:SETUP:SETUP:SETUP:SETUP: Connect the CH1 probe to amplifier input of the channel under test and set both at 500mV/div. 200mS/div. Connect the CH2 probe to amplifier output of the channel under test and set it at 10mV/div. 200mS/div. Set the audio generator at 1KHz sinus. 775mVRMS (0dB). Set the LEVEL potentiometers full clockwise. The load resistor is disconnected. CMRR ADJUSTMENTCMRR ADJUSTMENTCMRR ADJUSTMENTCMRR ADJUSTMENTCMRR ADJUSTMENT Temporarily disconnect pin 3 from pin 1 and short the pin 2 (positive input) and pin 3 (negative input) of XLR input socket. Adjust the trimmer R10 (channel A) or R21 (channel B) to obtain the minimum output level. Fig. 6Fig. 6Fig. 6Fig. 6Fig. 6 Trace A (5V/div.) Trace B (2V/div.) Fig. 8Fig. 8Fig. 8Fig. 8Fig. 8 Trace A (10V/div.) Fig. 7Fig. 7Fig. 7Fig. 7Fig. 7 Trace A (5V/div.) Trace B (2V/div.) Trace B (20V/div.) Trace A (20V/div.) Trace C (20V/div.) RadioFans.CN 收音机爱 好者资料库 J J J J J 4 4 4 4 4 GAIN ADJUSTMENTGAIN ADJUSTMENTGAIN ADJUSTMENTGAIN ADJUSTMENTGAIN ADJUSTMENT Re-set the input signal at pin 2 (positive input) and pin 3 (negative input) short with pin 1 (GND) of XLR input socket. Set CH2 scope at 500mV/div. and connect it to the output of INPUTS board (CN3 pin9 for channel A or CN3 pin7 for channel B). Set the input SENSITIVITY (SW1) at 1.75Vrms, adjust the trimmer R5 (channel. A) or R17 (channel B) to obtain the same amplitude of the scope signals. AMPLIFIER GAIN CHECKAMPLIFIER GAIN CHECKAMPLIFIER GAIN CHECKAMPLIFIER GAIN CHECKAMPLIFIER GAIN CHECK Set CH2 scope at 20V/div. and connect it to the amplifier output of the channel under test. By means of the SENSITIVITY switch check the output levels: at 775mV position the output voltage must be 501.5Vp and at 1.75V position must be 22.50.5Vp. AMPLIFIER BRIDGE MODE CHECKAMPLIFIER BRIDGE MODE CHECKAMPLIFIER BRIDGE MODE CHECKAMPLIFIER BRIDGE MODE CHECKAMPLIFIER BRIDGE MODE CHECK Set the amplifier in BRIDGE mode (input signal to channel A), connect the CH2 probe to the bridge output: the output voltage must be 973Vp. SIGNAL TO NOISE RATIO CHECKSIGNAL TO NOISE RATIO CHECKSIGNAL TO NOISE RATIO CHECKSIGNAL TO NOISE RATIO CHECKSIGNAL TO NOISE RATIO CHECK Disconnect the audio generator and short the input (pin 1,2,3 of XLR socket shorted) the output signal (noise) must be less 1mV. AdvicesAdvicesAdvicesAdvicesAdvices Check the channels one at time to determine which is right (note: if you have a spare amplifier module that you know as right, use it). If you have determinate that the problem is a short on a rail, you must check the output transistors. To determine which transistor devices are bad, use a soldering iron to lift one leg of each emitter pin and measure the emitter-collector resistance on each device. Unsolder and lift one leg of each base pin and check the base-collector resistance of each transistor and replace any that measure as a short. If all the transistors are OK, unsolder and lift one leg of each diode and check them. Check the circuit board for open foil traces. Use the Multimeter as Ohm-meter to check the resistors, particularly the base and emitter resistors of damaged transistor. If the input sinewave appears to be distorted during the negative cycle, you can assume that the problem is located somewhere in the circuitry of the positive low rail. If the positive cycle appears distorted, you can assume that the problem is in the circuitry of the negative low rail. If the high rails appear distorted or are not modulating as shown in figure, then the problem probably exists somewhere in the circuitry of the respec- tive (+ or -) defective high rail. Refer to the schematics. CH. BCH. A MIN. LOAD 4 WARNING ! RISK OF HAZARDOUS ENERGY MAKE PROPER SPEAKERS CONNECTIONS REFER TO OWNERS MANUAL BEFORE USING OUTPUTS HOT COLD GND WIRINGSENSITIVITY 1.75 V 0.775 V EARTH MODE BRIDGE P A R A L L E L S T E R E O BALANCEDBALANCED CH. BCH. A INPUTS AC 21 3 AC SER. MOD. MADE IN INDIA BRIDGE MIN. LOAD 8MIN. LOAD 4 PIN 1 PIN 1+ P P500 PROFESSIONAL POWER AMPLIFIER by DESIGNED AND ENGINEERED IN ITALY AVIS:RISQUE DE CHOC ELECTRIQUE-NE PAS OUVRIR RISK OF ELECTRIC SHOCK DO NOT OPEN CAUTION WARNING TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK DO NOT EXPOSE THIS PRODUCT TO PROTECTPROTECT SIGN/CLIPSIGN/CLIP BRIDGESTEREOPARALLEL AB P500500PROFESSIONAL POWER AMPLIFIER POWER ON 5 5 5 5 5 J J J J J J J J J J 6 6 6 6 6 7 7 7 7 7 J J J J J J J J J J 8 8 8 8 8 Spare Part ListSpare Part ListSpare Part ListSpare Part ListSpare Part List CodeRef.Description AccessoriesAccessoriesAccessoriesAccessoriesAccessories 277317Owners Manual P-Series AssemblyAssemblyAssemblyAssemblyAssembly 667644MSSDCR01Cover 667643MSSDCQ01Chassis 667642MSSEBB01Front Panel 667335MEAYA104Rear Spacer 657232HRDKBH51Level Knob 340048Cord Lock 238083FIN27341Transformer 500W 230Vac 177542MEATA102Handle 141200CONJK351Speakon Socket 130285Mains Cable (EU) 110294Slider Switch (Earth Lift) 110291SWTPR141Power Switch 080607KBPC25 25A 200V Rectifier Diode Bridge 778124FIN27361Cables Assembly Inputs AssembliesInputs AssembliesInputs AssembliesInputs AssembliesInputs Assemblies 768142768142768142768142768142FIN27305FIN27305FIN27305FIN27305FIN27305Sockets Board (Pcb#9603014)Sockets Board (Pcb#9603014)Sockets Board (Pcb#9603014)Sockets Board (Pcb#9603014)Sockets Board (Pcb#9603014) 140228CONJK151*Horizontal Jack Stereo Socket CONJK141*XLR Female Socket 768141768141768141768141768141FIN27302FIN27302FIN27302FIN27302FIN27302Inputs Board (Pcb#9602004)Inputs Board (Pcb#9602004)Inputs Board (Pcb#9602004)Inputs Board (Pcb#9602004)Inputs Board (Pcb#9602004) 110293*2sw 2pos Slider Switch 110255*6sw 3pos Vertical Slider Switch 100061*TL072 Dual J-Fet Operational Amplifier (replace BA4560 for service) 070245*100K 20% Vertical Linear Trimmer 070125*1K 20% Vertical Linear Trimmer 042625*15K0 1/4W 1% Metalized Film Resistor 042537*3K01 1/4w 1% Metalized Film Resistor 030085*2u2 50V 20% Vert Electrolytic Bipolar Capacitor Display AssembliesDisplay AssembliesDisplay AssembliesDisplay AssembliesDisplay Assemblies 768144768144768144768144768144FIN27306FIN27306FIN27306FIN27306FIN27306Led On/Off Board (Pcb#9610036)Led On/Off Board (Pcb#9610036)Led On/Off Board (Pcb#9610036)Led On/Off Board (Pcb#9610036)Led On/Off Board (Pcb#9610036) 768139768139768139768139768139FIN27304FIN27304FIN27304FIN27304FIN27304Display Board (Pcb#9610036)Display Board (Pcb#9610036)Display Board (Pcb#9610036)Display Board (Pcb#9610036)Display Board (Pcb#9610036) 090194*BC560 TO92 LN Pnp Transistor 080742*Led 3mm Wide Diffused Red-Grn 080710*Led 3mm 60deg Diffused Yel 080705*Led 3mm 60deg Diffused Red 074561RESVRD01*4K7 Linear Rotary Potentiometer Supplies & Protections AssemblySupplies & Protections AssemblySupplies & Protections AssemblySupplies & Protections AssemblySupplies & Protections Assembly 768140768140768140768140768140FIN27303FIN27303FIN27303FIN27303FIN27303Power Supplies & Protections Board (Pcb#9602002)Power Supplies & Protections Board (Pcb#9602002)Power Supplies & Protections Board (Pcb#9602002)Power Supplies & Protections Board (Pcb#9602002)Power Supplies & Protections Board (Pcb#9602002) 110307*Relay 24V / 2 Switch 5A 250V 110030*T10A Fuse 5x20mm (EU) 110023*T8A Fuse 5x20mm (EU) 110018*T6.3A Fuse 5x20mm (EU) 090920*MJE802 TO126 Npn Darl Transistor 090559*TIP122 TO220 Npn Darlington Transistor 090558*TIP127 TO220 Pnp Darlington Transistor 090194*BC560 TO92 LN Pnp Transistor 090183*BC550 TO92 LN Npn Transistor 080322*24V 1W 5% Zener Diode 080293*15V 1W 5% Zener Diode 080282*13V 1W 5% Zener Diode 080156*1N4002 1A 100V Rectifier Diode 080103*1N4148 100mA 75V Signal Diode 060475*680E 2W 10% Resistor 030891CAPELJ81*10000u 63V -10+50% Vert Electrolytic Capacitor FS 030888*10000u 80v -10+50% V Electrolytic Capacitor FS 020493*100n 250Vac MKP EMI Capacitor “Siemens” Power Channels AssemblyPower Channels AssemblyPower Channels AssemblyPower Channels AssemblyPower Channels Assembly 727588727588727588727588727588FIN27311FIN27311FIN27311FIN27311FIN27311Dual Power Amplifier Board (Pcb#9602003)Dual Power Amplifier Board (Pcb#9602003)Dual Power Amplifier Board (Pcb#9602003)Dual Power Amplifier Board (Pcb#9602003)Dual Power Amplifier Board (Pcb#9602003) 727595727595727595727595727595 * * * * * Power Amplifier Board (Pcb#9602003) with HeatsinkPower Amplifier Board (Pcb#9602003) with HeatsinkPower Amplifier Board (Pcb#9602003) with HeatsinkPower Amplifier Board (Pcb#9602003) with HeatsinkPower Amplifier Board (Pcb#9602003) with Heatsink 768143768143768143768143768143*Power Amplifier Board (Pcb#9602003) without HeatsinkPower Amplifier Board (Pcb#9602003) without HeatsinkPower Amplifier Board (Pcb#9602003) without HeatsinkPower Amplifier Board (Pcb#9602003) without HeatsinkPower Amplifier Board (Pcb#9602003) without Heatsink 230557*1uh Horizontal Coil For Amplifier 100931*MC34081 Single J-Fet Operational Amplifier 100928*TLP521-4 Quad Optocoupler 100004*LM3080 Operational Transconductance Amp. 090917*MJE350 TO126 Pnp Transistor 090916*MJE340 TO126 Npn Transistor 090201*2N5401 TO92 Pnp Transistor 090200*2N5550 TO92 Npn Transistor 090194*BC560 TO92 LN Pnp Transistor 090183*BC550 TO92 LN Npn Transistor 080293*15V 1W 5% Zener Diode 080261*10V 1W 5% Zener Diode 080245*7V5 1W 5% Zener Diode 080241*5V6 1W 5% Zener Diode 080171*FE6B 6A 100V Fast Recovery Diode 080156*1N4002 1A 100V Rectifier Diode 080103*1N4148 100mA 75V Signal Diode 070207*22K 20% Vertical Linear Trimmer 070084*220E 20% Vertical Linear Trimmer 070065*100