Sennheiser HME 26-600 User manual

Subject to alterations
Service manual
HMD/HMDC/HME 26
Broadcast
HMD 26-600SHME 26-600S
HME 26-600
HME 26-600-7
HME 26-100
HME 26-100-7
HME 26-100(4)
HME 26-600(4)
HMD 26-600
HMD 26-600-7
HMD 26-100
HMD 26-100-7
HMD 26-600-X3K1
HMDC 26-600
Headset variants
Cable variants
-6, -H-6
-7, -B-7
-X4F, -H-X4F
-X3K1, -H-X3K1
-X3K1-P48
-X5
Sennheiser electronic GmbH & Co. KG
Am Labor1, 30900 Wedemark, Germany
www.sennheiser.com 1/23
SA 100810
Revision 08/2011
Short description
These headsets have been designed for broadcast use, e.g. for outdoor broadcast and TV
applications.
Features
•Dynamic, closed headphones with supra-aural ear coupling
•Flip-away headphone allows single-sided listening (not for the HME/HMD 26-600S)
•Several microphone variants
•Flexible microphone arm, can be worn on either left or right-hand side
•Single-sided cable routing

HMD/HMDC/HME 26 Broadcast
08/2011 2/23
Safety requirements
Observe safety regulations.
Observe ESD instructions while handling electrostatically endangered components.
Only skilled persons are allowed to alter and repair. For repairs and exchanges only
approved components according to the current spare parts list are allowed.
For safety and certification reasons it is forbidden to alter the product without
authorization. Otherwise, the person who has altered the product is liable for any
consequential damage.
repairs/exchanges The following instructions for overhaul and testing must be followed.
In case of unusual problems please contact your Sennheiser service center support.
CAUTION
During SMD component soldering you may destroy them by using a
standard soldering iron for several seconds.
Only use adapted soldering tools when soldering SMD components.
SMD

Contents
HMD/HMDC/HME 26 Broadcast
08/2011 3/23
1 Product overview............................................................................................4
1.1 Headset................................................................................................................... 4
1.2 Operating control-B-7 (when using the HMDC 26) ....................................... 4
2 Technical data.................................................................................................5
2.1 Technical data HMD 26........................................................................................ 5
2.2 Technical data HMDC 26...................................................................................... 6
2.3 Technical data HME 26 ........................................................................................ 7
3 Exploded view.................................................................................................8
3.1 Exploded view of the complete unit ................................................................. 8
3.2 Exploded view of the headband module ......................................................... 9
3.3 Exploded view of the microphone cap module
(with microphone arm support and cable)9
3.4 Exploded view cable -B-7 (for HMDC 26)....................................................... 10
4 Test and alignment instructions ............................................................... 11
4.1 Measuring and test equipment ....................................................................... 11
5 Disassembly/Assembly .............................................................................. 12
5.1 Disassembly......................................................................................................... 12
5.2 Assembly.............................................................................................................. 14
6 Functional test............................................................................................. 19
6.1 Functional test of the headphones ................................................................. 19
6.2 Functional test of the microphone.................................................................. 19
6.3 Functional test ActiveGard™ (HMD/HME 26) ............................................... 20
6.4 Functional test NoiseGard™ (HMDC 26)......................................................... 20
7 Circuit diagrams........................................................................................... 21
7.1 Cable and connector assignment .................................................................... 21
7.2 PCB of the acoustic units of the HMDC 26 ..................................................... 22
7.3 PCB of the acoustic units of the HMD/HME 26 ............................................. 23

HMD/HMDC/HME 26 Broadcast
08/2011 4/23
1 Product overview
1.1 Headset
쐃Split headband
쐇Padding for the split headband (available as accessory)
쐋Cap microphone side
쐏Microphone arm support of the cap (not visible)
쐄Connecting cable with headset connector
(see “Cable and connector assignment”, page 21)
쐂Microphone arm,
the visualization depends on the the microphone type, see Technical Data
쐆Cap non microphone side/ temple support (HME/HMD 26-600S)
쐊Earpad
쐎ActiveGard switch (HME/HMD 26 only)
쐅Flip-away hinge for flipping away the cap not microphone side
(not HME/HMD 26-600S)
1.2 Operating control-B-7 (when using the HMDC 26)
쐃NoiseGard™ LED
쐇NoiseGard™ ON/OFF switch
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HMD/HMDC/HME 26 Broadcast
08/2011 5/23
2 Technical data
2.1 Technical data HMD 26
2.1.1 Headphones
Transducer principle ___________________dynamic, closed
Ear coupling _________________________supra-aural
Frequency response____________________20 Hz to 18 kHz
Impedance
HMD 26-600 ____________________300 Ωmono/600 Ωstereo
HMD 26-600S ___________________600 Ωmono
HMD 26-100 ____________________50 Ωmono/100 Ωstereo
Characteristic at 1 kHz, 1 V
HMD 26-600/-600S _______________107 dB SPL
HMD 26-100
(ActiveGard is switched off) ________115 dB SPL
Max. SPL at 1 kHz
(ActiveGard is switched on) _____________105 dB SPL
HMD 26-600/-600S at 200 mW _____127 dB SPL
HMD 26-100 at 200 mW
(ActiveGard is switched off) ________128 dB SPL
THD at 1 kHz _________________________< 0.5%
Contact pressure
HMD 26-600/-100 ________________approx. 3.6 N
HMD 26-600S ___________________approx. 4.0 N
2.1.2 Microphone
Type ______________________________BMD 424
Transducer principle of the BMD 424_______dynamic, noise-compensating
Pick-up pattern _______________________hyper-cardioid
Frequency response____________________40 to 16,000 Hz
Output voltage at 1 kHz ________________0.4 mV/Pa
Impedance___________________________300 Ω
2.1.3 General data
Ambient temperature
Operation_______________________–15 °C to 55 °C
Storage ________________________–55 °C to 70 °C
Weight without cable
HMD 26-600/-100 ________________approx. 200 g
HMD 26-600S ___________________approx. 130 g
Cable and connector assignment__________see page 21