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SA 050418

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Sennheiser electronic GmbH & Co. KG • 30900 Wedemark
Phone: +49 (5130) 600 0 • Fax: +49 (5130) 600 300

1/53

MKH 20...70

service manual

MKH 20

MKH 30

MKH 40

MKH 50

MKH 60

MKH 70

Summary of Contents for MKH 20

Page 1: ...SA 050418 Subject to alterations Sennheiser electronic GmbH Co KG 30900 Wedemark Phone 49 5130 600 0 Fax 49 5130 600 300 1 53 MKH 20 70 service manual MKH 20 MKH 30 MKH 40 MKH 50 MKH 60 MKH 70 ...

Page 2: ...r and repair For repairs and exchanges only approved components according to the current spare parts list ere allowed It is forbidden to alter the product unauthorized If not observed the adaptor is legally liable for possible results of damage repairs exchanges The following instructions for overhaul and testing must be followed In case of unusual problems please contact your Sennheiser distribut...

Page 3: ...5 MKH 20 component side 15 MKH 20 circuit diagram 16 MKH 30 P 48 17 Brief description 17 Features 17 Controls 18 Technical Data 18 Exploded view 20 Schematic representations 21 MKH 30 solder side 21 MKH 30 component side 21 MKH 30 circuit diagram 22 MKH 40 P 48 23 Brief description 23 Features 23 Controls 24 Technical Data 24 Exploded view 26 Schematic representations 27 MKH 40 solder side 27 MKH ...

Page 4: ...cal Data 36 Exploded view 38 Schematic representations 40 MKH 60 solder side 40 MKH 60 component side 40 MKH 60 circuit diagram 41 MKH 60 component side new 42 MKH 60 solder side new 42 MKH 60 circuit diagram new 43 MKH 70 1 P 48 45 Brief description 45 Features 45 Controls 46 Technical Data 46 Exploded view 48 Schematic representations 50 MKH 70 solder side 50 MKH 70 component side 50 MKH 70 circ...

Page 5: ...g measures according to the following test instructions Checking the microphone capsule To check the microphone capsule disassemble the microphone first For the MKH 60 and the MKH 70 unscrew the sound inlet first Loosen the two countersunk head screws on the housing and then use the XLR con nector pins to carefully press out the frame together with the capsule To further disassemble the microphone...

Page 6: ... put in parentheses Demodulator Via L2 the RF bridge signal is supplied to the demodulator with D1 D2 and C5 C6 or C3 C5 and the symmetrical windings 5 6 and 7 8 of L1 The demodulator operates as a synchronous rectifier putting through the RF signal of L2 to C6 or C5 during one half wave while blocking it during the other half wave The rectified voltage at C5 or C3 biases both D1 and D2 to such an...

Page 7: ... R9 causes a treble emphasis with a maximum at 20kHz In addition C9 R11 and R12 cause a bass emphasis In the S2 standard position R11 and R12 are connected in parallel If S2 is opened bass roll off only R12 is effective and the bass emphasis is reduced R13 and C8 correct the frequency response in the center frequency range AF amplifier MKH60 70 The amplifier integrated in both the MKH60 and the MK...

Page 8: ...lies half of the operating current to the microphone The divided operating current is merged by the two resistors R20 and R21 or R18 R19 with identical resistances The current flows back to the phantom supply source via the amplifier circuit MKH60 70 via both amplifier stages the oscillator and the cable shield microphone ground Since the operating current is stabilized by the oscillator circuit t...

Page 9: ... supply device is not 48V the deviation from the desired value has to be identical 쐇 Current consumption microphone Check voltages via R20 and R21 desired value in each case 3 3V corresponds to a current of 1mA in each case both voltages have to be identical 쐋 Balancing Check the voltage between the measuring points A and B desired value 0V If the value is not 0V rotate the coil core of L1 until t...

Page 10: ...urrent consumption microphone Check voltages via R18 and R19 desired value in each case 2 2V corresponds to 1mA in each case both voltages have to be identical 쐋 Balancing Check the voltage between the measuring points A and B desired value 0V If the value is not 0V rotate the coil core of L1 until the voltage is 0V 쐏 Operating voltage output stage Check voltage via D4 desired value 4 5V Check vol...

Page 11: ...0 P 48 is a high frequency condenser microphone with omnidirectional characteristic Features Very low noise for highly dynamical recordings Distortion free transmission of sound pressures of up to 142dB Transmission range 20 to 20000Hz Balanced transformer free signal decoupling Switchable diffuse field correction for recordings outside of the diffuse field distance Switchable pre attenuation ...

Page 12: ...er free Electrical impedance at 1kHz ____________ 150Ω Min terminating impedance ____________ 1000Ω Pre attenuation ______________________ 10dB switchable Diffuse field correction_________________ switchable Infrasonic attenuation _________________ 18dB oct below 20Hz Plug in connection ____________________ XLR3 Connector layout _____________________ 1 housing 2 AF 3 AF Power supply ______________...

Page 13: ...MKH 20 P 48 04 2005 13 53 Frequency response Polar diagram diffuse field correction activated Wirkung der Diffusfeldkorrektur ...

Page 14: ...ead insert 003 Damping ring 004 Countersunk screw hexagon socket M2 5x4 005 Housing MKH20 006 Metal screw ST2 2x6 5 007 Connecting shell for XLR3 008 Chassis complete 009 Countersunk screw M2x3 010 Condenser capsule KS20 011 Type plate MKH20 012 Brace 013 IC mounting DIL6 014 Plate 015 O ring 18x1 for condenser capsule version 2 S001 Slide switch S002 Slide switch ...

Page 15: ...MKH 20 P 48 04 2005 15 53 Schematic representations 3 6079 1L2 3 6079 1L2 MKH 20 component side MKH 20 solder side ...

Page 16: ...MKH 20 P 48 16 53 04 2005 MKH 20 circuit diagram ...

Page 17: ...P 48 Brief description The MKH 30 P 48 is a high frequency condenser microphone with bidirectional characteristic Features Very low noise for highly dynamical recordings Distortion free transmission of sound pressures of up to 142dB Transmission range 40 to 20000Hz Balanced transformer free signal decoupling Switchable roll off filter Switchable pre attenuation ...

Page 18: ...anced transformer free Electrical impedance at 1kHz ____________ 150Ω Min terminating impedance ____________ 1000Ω Pre attenuation ______________________ 10dB switchable Low cut filter cut off _________________ 12dB oct below 30Hz Roll off filter ________________________ additional 4dB reduction at 50Hz Plug in connection ____________________ XLR3 Connector layout _____________________ 1 housing 2...

Page 19: ...MKH 30 P 48 04 2005 19 53 Frequency response Polar diagram bass roll off activated Wirkung der schaltbaren Tiefendämpfung ...

Page 20: ...capsule KS30 003 Thread ring 004 Housing MKH30 005 Countersunk screw hexagon socket M2 5x4 006 Countersunk screw M2x3 007 Chassis complete 008 Brace 009 Connecting shell for XLR3 010 Metal screw ST2 2x6 5 011 Type plate MKH30 012 IC mounting DIL6 013 Plate 014 Easy release clamp 015 Thread insert 016 O ring 18x1 for condenser capsule version 2 S001 Slide switch S002 Slide switch ...

Page 21: ...MKH 30 P 48 04 2005 21 53 Schematic representations MKH 30 component side MKH 30 solder side 3 6079 1L2 3 6079 1L2 blue marking ...

Page 22: ...MKH 30 P 48 22 53 04 2005 MKH 30 circuit diagram ...

Page 23: ...al MKH 40 P 48 Brief description The MKH 40 P48 is a high frequency condenser microphone with cardioid characteristic Features Very low noise for highly dynamical recordings Largely frequency independent directional characteristic Broad transmission range Balanced transformer free signal decoupling Switchable roll off filter Switchable pre attenuation ...

Page 24: ...nced transformer free Electrical impedance at 1kHz ____________ 150Ω Min terminating impedance ____________ 1000Ω Pre attenuation ______________________ 10dB switchable Low cut filter cut off _________________ 12dB oct below 30Hz Roll off filter ________________________ additional 4dB reduction at 50Hz Plug in connection ____________________ XLR3 Connector layout _____________________ 1 housing 2 ...

Page 25: ...MKH 40 P 48 04 2005 25 53 Frequency response Polar diagram bass roll off activated Wirkung der schaltbaren Tiefendämpfung ...

Page 26: ... clamp 002 Thread insert 004 Countersunk screw hexagon socket M2 5x4 005 Housing MKH40 006 Damping silk 007 Type plate MKH40 008 Metal screw ST2 2x6 5 009 Connecting shell for XLR3 010 Chassis complete 011 Countersunk screw M2x3 012 Condenser capsule KS40 014 Brace 015 IC mounting DIL6 016 Plate 017 O ring 18x1 S001 Slide switch S002 Slide switch ...

Page 27: ...MKH 40 P 48 04 2005 27 53 Schematic representations MKH 40 component side MKH 40 solder side 3 6079 1L2 3 6079 1L2 red marking ...

Page 28: ...MKH 40 P 48 28 53 04 2005 MKH 40 circuit diagram ...

Page 29: ...KH 50 P 48 Brief description The MKH 50 P 48 is a high frequency condenser microphone with hyper cardioid characteristic Features Very low noise for highly dynamical recordings Largely frequency independent directional characteristic Broad transmission range Balanced transformer free signal decoupling Switchable roll off filter Switchable pre attenuation ...

Page 30: ...___________ balanced transformer free Electrical impedance at 1kHz ____________ 150Ω Min terminating impedance ____________ 1000Ω Pre attenuation ______________________ 10dB switchable Low cut filter cut off _________________ 12dB oct below 30Hz Roll off filter ________________________ additional 4dB reduction at 50Hz Plug in connection ____________________ XLR3 Connector layout __________________...

Page 31: ...MKH 50 P 48 04 2005 31 53 Frequency response Equalization Polar diagram ...

Page 32: ...003 Thread ring 004 Damping silk 005 Dust protection 006 Housing MKH50 007 Countersunk screw hexagon socket M2 5x4 008 Countersunk screw M2x3 009 Chassis complete 010 Brace 011 Connecting shell for XLR3 012 Metal screw ST2 2x6 5 013 Type plate MKH50 014 IC mounting DIL6 015 Plate 016 Easy release clamp 017 Threaded insert 018 O ring 18x1 for condenser capsule version 2 S001 Slide switch S002 Slide...

Page 33: ...MKH 50 P 48 04 2005 33 53 Schematic representations MKH 50 component side 3 6079 1L2 3 6079 1L2 MKH 50 solder side yellow marking ...

Page 34: ...MKH 50 P 48 34 53 04 2005 MKH 50 circuit diagram ...

Page 35: ...1 P 48 service manual MKH 60 1 P 48 Brief description The MKH 60 1 P 48 is a high frequency condenser microphone with hyper cardioid lobe characteristic Features Low noise for highly dynamical recordings Uniform directional characteristic Broad transmission range Switchable pre attenuation 10dB Switchable filters roll off and presence ...

Page 36: ...__ balanced transformer free Electrical impedance at 1kHz ____________ 150Ω Min terminating impedance ____________ 1000Ω Pre attenuation ______________________ 10dB switchable Low cut filter cut off _________________ 18dB oct below 50Hz Roll off filter ________________________ additional 3dB reduction at 70Hz Presence filter _______________________ 5dB emphasis at 10kHz Plug in connection ________...

Page 37: ...MKH 60 1 P 48 04 2005 37 53 Frequency response Equalization Polar diagram ...

Page 38: ...MKH 60 1 P 48 38 53 04 2005 Exploded view 001 002 005 003 004 006 013 014 007 018 019 022 008 018 010 011 S002 016 023 024 020 015 S001 S003 017 ...

Page 39: ... 010 Connecting shell for XLR3 011 Cheese head screw M2x5 012 Type plate MKH60 1 013 Housing MKH60 014 Countersunk screw hexagon socket M2 5x4 015 O ring 18x1 016 PCB assembly MKH60 017 Base for IC 018 Cheese head screw M1 7x3 019 Ring 020 Sheet metal 16 8x11 4 021 Type plate frequency as order 022 Socket contact with rubber ring 023 Cover 103 4x19 5x3 6 024 Cheese head screw M1 7x6 S001 Slide swi...

Page 40: ...MKH 60 1 P 48 40 53 04 2005 Schematic representations MKH 60 component side MKH 60 solder side ...

Page 41: ...MKH 60 1 P 48 04 2005 41 53 MKH 60 circuit diagram ...

Page 42: ...13 TP12 TP11 TP10 TP1 S3 S2 S1 L5 L4 L3 L2 L1 D8 D7 C8 C7 C6 C3 C18 C17 C16 C14 C13 C12 L7 L6 C22 C21 MKH 60 component side new 57820 L Date Time 15 02 2005 09 46 R9 R8 R7 R6 R5 R4 R3 R2 R19 R18 R17 R16 R15 R14 R13 R12 R11 R10 R1 Q5 Q4 Q3 Q2 Q1 D6 D5 D4 D3 D2 D1 C9 C5 C4 C2 C15 C11 C10 C1 BF2 R21 R20 C20 C19 BF1 MKH 60 solder side new ...

Page 43: ...1 21KF R13 1 21KF R18 2 21KF R19 2 21KF R20 68 1RF R21 68 1RF R3 332RF R4 332RF R6 15KF R7 15KF R8 475KF R9 39 2RF R10 15KF R11 56 2KF R14 3 32KF R15 33 2KF R16 22 1KF R17 33 2KF MMBT5087LT1 Q4 MMBT5087LT1 Q3 rs sw rs rs rt gn sw gn rt sw rs rt rs sw rs gn sw gn L1 1 2 3 Geh H V MKH 60 70 B A NTC 24V HF 41V 41V 41V 1 3V 1 1V HF 29V 16V HF 0 75V 0 55V 30 5V MKH70 9 5V 10dB 34 5V 36 5V 39V 41V 24V H...

Page 44: ...MKH 60 1 P 48 44 53 04 2005 ...

Page 45: ... P 48 service manual MKH 70 1 P 48 Brief description The MKH 70 1 P 48 is a high frequency condenser microphone with hyper cardioid lobe characteristic Features Low noise for highly dynamical recordings Uniform directional characteristic Broad transmission range Switchable pre attenuation 10dB Switchable filters roll off and presence ...

Page 46: ..._____________________ balanced transformer free Electrical impedance at 1kHz ____________ 150Ω Min terminating impedance ____________ 1000Ω Pre attenuation ______________________ 10dB switchable Low cut filter cut off _________________ 18dB oct below 50Hz Roll off filter ________________________ additional 3dB reduction at 70Hz Presence filter _______________________ 5dB emphasis at 10kHz Plug in ...

Page 47: ...MKH 70 1 P 48 04 2005 47 53 Frequency response Equalization Polar diagram ...

Page 48: ...MKH 70 1 P 48 48 53 04 2005 Exploded view 013 014 004 003 002 001 005 006 007 018 019 022 008 018 010 011 S002 016 023 024 020 015 S001 S003 017 ...

Page 49: ...9 Brace 010 Connecting shell for XLR3 011 Cheese head screw M2x5 012 Type plate MKH70 1 013 Housing MKH70 014 Countersunk screw hexagon socket M2 5x4 015 O ring 18x1 016 Printed circuit board assy MKH70 017 Base for IC 018 Cheese head screw M1 7x3 019 Ring 020 Sheet metal 16 8x11 4 021 Type plate frequency as order 022 Socket contact with rubber ring 023 Cover 103 4x19 5x3 6 024 Cheese head screw ...

Page 50: ...21 TP19 TP4 TP5 TP8 TP12 TP11 TP9 TP10 TP14 TP13 TP16 TP18 L5 S3 S2 S1 L4 L3 L2 L1 C18 C17 C16 C14 C13 C12 C8 C7 C6 C3 MKH 70 component side 57820 L R21 R20 R19 R18 R17 R16 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 Q5 Q4 Q3 Q2 Q1 D6 D5 D4 D3 D2 D1 C20 C19 C15 C11 C10 C9 C5 C4 C2 C1 BF2 BF1 MKH 70 solder side ...

Page 51: ...MKH 70 1 P 48 04 2005 51 53 TP21 TP1 TP5 TP6 TP2 TP4 TP18 TP16 TP15 TP14 TP13 TP8 TP10 TP9 TP11 TP12 TP20 TP19 MKH 70 circuit diagram ...

Page 52: ...13 TP12 TP11 TP10 TP1 S3 S2 S1 L5 L4 L3 L2 L1 D8 D7 C8 C7 C6 C3 C18 C17 C16 C14 C13 C12 L7 L6 C22 C21 MKH 70 component side new 57820 L Date Time 15 02 2005 09 46 R9 R8 R7 R6 R5 R4 R3 R2 R19 R18 R17 R16 R15 R14 R13 R12 R11 R10 R1 Q5 Q4 Q3 Q2 Q1 D6 D5 D4 D3 D2 D1 C9 C5 C4 C2 C15 C11 C10 C1 BF2 R21 R20 C20 C19 BF1 MKH 70 solder side new ...

Page 53: ... 21KF R13 1 21KF R18 2 21KF R19 2 21KF R20 68 1RF R21 68 1RF R3 332RF R4 332RF R6 15KF R7 15KF R8 475KF R9 39 2RF R10 15KF R11 56 2KF R14 3 32KF R15 33 2KF R16 22 1KF R17 33 2KF MMBT5087LT1 Q4 MMBT5087LT1 Q3 rs sw rs rs rt gn sw gn rt sw rs rt rs sw rs gn sw gn L1 1 2 3 Geh H V MKH 60 70 B A NTC 24V HF 41V 41V 41V 1 3V 1 1V HF 29V 16V HF 0 75V 0 55V 30 5V MKH70 9 5V 10dB 34 5V 36 5V 39V 41V 24V HF...

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