Bose T5 User manual

Service Manual
Reference Number 350006-SM Rev. 00
©2016 Bose Corporation
T5 Tactical Headset

2
PROPRIETARY INFORMATION
THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION OF
BOSE CORPORATION WHICH IS BEING FURNISHED ONLY
FOR THE PURPOSE OF SERVICING THE IDENTIFIED BOSE
PRODUCT BYAN AUTHORIZED SERVICE CENTERAND SHALL
NOT BE REPRODUCED OR USED FORANY OTHER PURPOSE.
CAUTION: The Bose®T5 Tactical Headset contains no user serviceable parts. To prevent
warranty infractions, refer servicing to warranty service stations or factory service.
CONTENTS
IMPORTANT NOTE: These products are RoHS compliant. Use ONLY lead free solder when
making repairs.
Electrostatic Discharge Sensitive (ESDS) Device Handling .........................................................3
Part List Notes...................................................................................................................................3
Specifications....................................................................................................................................4
Product Description.................................................................................................................... 5-10
Single Comm Module Controls........................................................................................................6
Dual Comm Module Controls...........................................................................................................6
Manufactured Versions ..................................................................................................................11
Packaging Part Lists, T5 Headset, All Versions ...........................................................................11
User Replaceable Parts List...........................................................................................................11
System Configurations............................................................................................................. 12-13
Cables and Replacement Parts......................................................................................................14
Disassembly Procedures ......................................................................................................... 15-19
Test Procedures ........................................................................................................................ 20-26
Definitions........................................................................................................................................20
Troubleshooting ........................................................................................................................ 27-29
Service Manual Revision History...................................................................................................30

3
ELECTROSTATIC DISCHARGE SENSITIVE (ESDS)
DEVICE HANDLING
This unit contains ESDS devices. We recommend the following precautions when repairing,
replacing or transporting ESDS devices:
• Perform work at an electrically grounded work station.
•Wear wrist straps that connect to the station or heel straps that connect to conductive floor
mats.
•Avoid touching the leads or contacts of ESDS devices or PC boards even if properly grounded.
Handle boards by the edges only.
•Transport or store ESDS devices in ESD protective bags, bins, or totes. Do not insert unpro-
tected devices into materials such as plastic, polystyrene foam, clear plastic bags, bubble wrap
or plastic trays.
PART LIST NOTES
1. The individual parts located on the PCB are listed in the part list.
2. This part is referenced for informational purposes only. It is not stocked as a repair part.
Refer to the next higher or lower level assembly for a replacement part.
3. This part is critical for safety purposes. Failure to use a substitute replacement with the
same safety characteristics as the recommended replacement part might create shock, fire and/
or other hazards.

4
SPECIFICATIONS
Bose®T5 TECHNICAL INFORMATION OVERVIEW
Mono and stereo available Single Comm and Dual Comm options
Weight (on head)
Control Module Weight
Dual Comm radio or intercom cables
455g
300g
120g (max/each)
Nominal Headband Clamping Force
Ear cup to Control Module Cable Length
2.1 +/- 0.1 lbs.
420 +/- 50 mm
Push-to-talk (PTT) on control module One momentary PTT switch for single comm
Two momentary PTT switches for dual comm
Live Mic Switch
2-position (on/off) toggle type switch, used to transmit
continuously within the intercom
ANR ON/OFF on control module 2-position (on/off) toggle type switch, powers headset in
dismounted operations
Talk-through (TTC switch
User-selectable, 4 position rotary, Binaural
Position one: off
Position two: 0db gain
Position three: medium gain
Position four: high gain
Battery Power
Current Draw
2 AA batteries
ANR Only: 40 hours minimum
TT Only: 100 hours minimum
ANR and TT: 30 hours minimum
16 mA RMS nominal at 24v
Operating noise environment Full ANR performance up to 123 dBSPL.
Reduced ANR from 124dBSL up to 130 dBSPL Max
Earphone sensitivity 104 ± 3dB SPL (active) for a 0±0.1 dBV input
94 ± 4dB SPL (bypass)
Input Impedance 1000±10% per channel (binaural)
500±10% (monaural)
Attenuation Performance will vary depending on the vehicle noise
profile and crew position.
Boom microphone Electret or Dynamic
Temperature Rating -40oC to +65oC Operating
-57oC to +71oC Storage
EMI MIL-STD-461F

5
PRODUCT DESCRIPTION
OVERVIEW
The Bose®T5 Tactical Headset (T5TH) offers an unsurpassed combination of full-spectrum
noise reduction, comfort and clear audio in an ergonomic and rugged form factor that is compat-
ible with a variety of helmets, intercoms and radio systems. The optional dual-communications
designed control module provides additional mission flexibility, which allows soldiers to easily
adapt the headset to fit specific mission needs.
The T5 Tactical Headset is designed to be used by infantry and other military personnel who are
primarily operating in and around tactical wheeled vehicles. These users engage in mission-
critical communications and require effective noise reduction. Interpersonal communication and
situational awareness are paramount, so they value products that are operationally flexible for
mounted and dismounted use cases without sacrificing hearing protection.
KEY BENEFITS
•Clear, two-way communication provides increased situational awareness via intercom, radio
and Talk-Through feature.
•Reduction of both continuous and impulse noise provides hearing protection and allows for
increased focus on mission-critical tasks and information.
•Certain configurations can support simultaneous communications with two different devices.
•Improved ergonomic design supports both mounted and dismounted operations, and the
seamless transition between the two.
•Designed to fit securely and comfortably under combat helmets to support longer mission
profiles.
•Designed for rugged combat use while being intuitive and easy to use with limited training.
•Easily field-repairable and upgradeable.

6
PRODUCT DESCRIPTION
Single Comm Module Controls
Dual Comm Module Controls

7
The T5 headset is capable of working in noise environments with sound pressure levels up to
115dB(C) SPL which means it is most useful in small and large wheeled vehicles as well as
many fixed and rotary wing aircraft.
The T5 headset consists of four main assemblies:
1. An active noise canceling headphone (two ear cups with ear cushions)
2. A suspension system (Napeband with over-the-head Velcro straps to support the weight)
3. A control cable assembly which provides power management, houses the necessary user
interface controls and adapts the headphone to the customer’s needs (by changing cables
to be compatible with desired source). The control cable assembly can be removed from the
earcups and replaced in the field.
4. A noise canceling boom microphone enabling communications. The microphone can be
easily replaced in the field.
The earcups each contain external-facing microphones and circuitry to allow Talk-Through, or
the ability to monitor external sounds such as speech without having to lift the earcups off of the
ear. This talk-through (TT) circuit limits external sounds to be no greater than 85dB at the ear.
The T5 headset has a volume control for the talk-through feature with volume settings will be
OFF; unamplified, medium amplification and high amplification. In all settings, the above men-
tioned 85dB limit is enabled.
The ear cushions used on the headset contribute to the performance as well as the overall
comfort of the headset. The ear cushions consist of polyurethane foam inside a polyurethane
film.
The napeband consists of a single, arc shaped spring formed to tuck behind the nape of the
user’s neck and head and to provide the desired clamping force. Two yokes connect the spring
to the earcups. The assembly is adjustable to fit most head sizes. The yokes and earcup
interface allow for rotation in 2 axes in order to allow optimum fit for performance as well as for
comfort. Additionally, the assembly includes a soft pad to provide cable routing and a comfort-
able fit behind the head for extended wear periods. The napeband / yoke assembly can be
completely disconnected from the earcups for replacement.
The control cable mates to the bottom of the left ear cup via a connector and housing that is
screwed to the earcup for robustness. This housing also mounts the flexible gooseneck boom
with integral noise canceling boom microphone. The control module contains a smart power
management system which can power the headset off of an external (vehicle) power source or
can use the on-board 2 AA batteries. In either case, the headset is fully functional to provide
active noise reduction (ANR), clear two way communications and talk-through capability. The
headset is also configured to provide passive noise reduction and clear two way communica-
tions when there is no power source (fail safe mode). The control module is configurable via
cable selection to enable connection of up to two input sources at any one time including inter-
coms, portable communication radios or other auxiliary audio or communication devices.
The control module also includes an integrated clothing clip that enables the module to be
securely mounted to a variety of clothing or equipment in a variety of orientations that best suit
the application at hand. The clothing clip can be mounted on both the front and the back face of
the control module in order to facilitate operation with either the left or the right hand or to cater
to different user preferences.
PRODUCT DESCRIPTION

8
PRODUCT DESCRIPTION
The control module switches and buttons are designed to be easily operated while wearing
typical work gloves with a material thickness of up to 3mm. They are also designed to provide
tactile feedback during operation and configured such that the mode of the switch can be
recognized visually or by feel.
The switches and their functions include:
1. Push to Talk (PTT) switch(es) (Momentary-Off)
2. 4-position rotary switch Talk Through (TT) control. The Talk Through circuit can be
powered by either the intercom (if applicable) or the 2-AA batteries in the control module.
3. Battery powered Active Noise Reduction (ANR) Switch (On-Off)
4. ICS Mic live Switch (Live-Mic, Mic-Off) This switch is used to enable continuous active
(latched) PTT mode for Intercom communications.
The boom microphone is serviceable and replaceable in the field. It is a dynamic microphone
which consists of a flexible gooseneck boom and a noise cancelling dynamic microphone
capsule. The Boom Microphone output is specific to the device it is attached to and is achiev-
able by selecting the appropriate cable. Some options may include a pass-through while others
may include a +24dB gain to simulate an electret microphone’s output level. If gain is needed,
the power is provided by the input device OR from the control module depending on the specific
input cable. Some options may include a pass-through dynamic 150 ohm, single ended or
differential microphone.
Operation Modes (Power Compatibility)
The power modes listed below are determined by the combination of cables plugged into the
device as well as voltages that are present in different locations or vehicles. Any combination of
power modes based on input connections or signals can be configured within the electronics of
the control module including but not limited to the following scheme.
External Power Source
• Unpowered (0 – 6.0 VDC )
• Battery powered ANR (2-AA batteries)
• Gain switchable Talk Through only
• Selectable Output Level and Frequency Response (Both parameters follow the state
of ANR and/or Talk-Through)
• Boom Microphone Output is specific to device it the is attached to and is configured
inside the input cable. Some options may include a pass through while others may
include a +24dB gain to simulate an electret microphone’s output level. If gain is
needed, the power is provided by the input device OR from the control module
depending on the specific input cable.
Low Power (6.1 - 13.5 VDC)
• Battery powered ANR
- ANR Switch position has no effect
• Gain switchable Talk Through

9
Operation Modes (Power Compatibility) (continued)
Intercom Power (13.6 – 32.0 VDC)
• Battery powered ANR
- ANR Switch does not operate
• Selectable Gain switchable Talk Through
• Boom Microphone Output is specific to device it is attached to and is configured inside the
input cable. Some options may include a pass through while others may include a +24dB
gain to simulate an electrets level. If gain is needed, the power is provided by the input
device OR from the control module depending on the specific input cable.
Battery Power (2x 1.5V AA ;1.8 – 3.2 VDC)
• ANR Switch OFF and Talk Through Switch OFF
- ANR off
- Talk Through off
- Unpowered Output Level and Frequency Response
- Boom microphone output depends on cable and device it is attached to.
• ANR Switch ON and Talk Through Switch OFF
- ANR on
- Talk Through off
- Powered Output Level and Frequency Response
- Boom microphone output depends on cable and device it is attached to.
• ANR Switch ON and Talk Through Switch in any ON position
- ANR on
- Talk Through on
- Powered Output Level and Frequency Response
- Boom microphone output depends on cable and device it is attached to.
• ANR Switch OFF and Talk Through Switch in any ON position
- ANR off
- Talk Through on
- Powered Output Level and Frequency Response
- Boom microphone output depends on cable and device it is attached to.
Operation Modes (Audio Management) Dual Comm Versions:
The headset is designed to support multiple audio sources through ports located at the bottom
of the in-line control module. The behavior of each port has been designed to support a wide
range of applications. Any combination and presentation of input and output audio signals can
be configured within the electronics of the control module, including but not limited to the follow-
ing scheme.
Port 1 is intended to be the primary communications port and can support binaural or mon-
aural sources. When the source is monaural, the cable for that device is wired such that the
monaural signal is paralleled so that it is made compatible with the binaural connection and the
user will always hear the audio from Port 1 in both ears. Whenever Port 1 is connected, press-
ing PTT 1 shorts the control line to the Port 1 source which enables transmission of the boom
microphone signal to the Port 1 source. If there is no source connected to Port 1, nothing
happens when PTT 1 is pressed.
PRODUCT DESCRIPTION

10
Operation Modes (Audio Management) Dual Comm Versions (continued):
Port 2 is intended to be a secondary communications port. The presentation of this source’s
audio to the headset depends upon the presence of a cable plugged into Port 1.
If Port 1 has a cable plugged in, the audio from the Port 2 device will only be presented to the
left earcup. In order to properly mix the audio between the multiple sources while maintaining
the dynamic range of the headset, the two signals will each be reduced by 6dB. The reduction
will occur as soon as the second cable is attached to the port on the bottom of the control
module .
If Port 1 does not have a cable plugged in, the audio from the Port 2 device will be presented to
both earcups and will not be reduced by 6dB.
Binaural devices may be connected to Port 2, however the cable connecting this type of source
to the control module will mix the two separate channels onto one signal line and present the
device as a mono device to the headset. Whenever Port 2 has a cable connected to it, pressing
PTT 2 shorts the control line to ground of the Port 2 source which enables transmission of the
boom microphone signal to the Port 2 source. If there is no cable connected to Port 2, nothing
happens when PTT 2 is pressed. The “Mic live” switch has no effect on any Port 2 device under
any configuration.
The table below describes how the headset manages the multiple audio sources based on what
cables are connected as well as how the PTT buttons function. An N/A in a cell means there is
no cable connected or there is no function. There are many variations of this that are possible.
PRODUCT DESCRIPTION
Mode of operation Port 1 Port 2 Left Earcup Right Earcup
Unpowered X N/
A
Port 1 Port 1
Unpowered N/A X Port 2 Port 2
Unpowered X X Port 1 + Port 2 Port 1 + Port 2
Battery Powered X N/A Port 1 Port 1
Battery Powered N/A X Port 2 Port 2
Battery Powered X X Port 1 Port 2
ICS powered 6-32 V X N/A Port 1 Port 1
ICS powered 6-32 V X X Port 1 + Port 2 Port 1

11
USER REPLACEABLE PARTS LIST
PACKAGING PART LISTS
T5 Headset, All Versions
MANUFACTURED VERSIONS
Item
Number Description Part Number Qty.
1 HDST/MODASSY, SINGLE COMM, MONAURAL
HDST/MOD ASSY, SINGLE COMM, BINAURAL
HDST/MODASSY, T5, DUALCOMM
350006-1100
350006-1200
350006-2000
1
2 CARTON, RSC, 9.00X7.00X5.25, C 277035-01 1
3 CARTON, RSC, 19.00X15.00X12.13, C 277036-01 1
4 BAG, POLY, 16x14 178245-1 1
5 PKG, 3/16 HIGH BUBBLE COHESIVE 196054 2
6 BAG, POLY, 3x7x.18 BUBBLE 149277 2
7 BATTERY, AA SIZE, PAI
R
263269-002 1
8 GUIDE, T5, SINGLE COMM
GUIDE, T5, DUAL COMM 355885-0010 354584-0010 1

V
ersion Description Material Master / SKU Numbe
r
HDST/MOD ASSY, SINGLE COMM, MONAURAL 349999-1100
HDST/MOD ASSY, SINGLE COMM, BINAURAL 349999-1200
HDST/MOD ASSY, T5, DUAL COMM 349999-2000
HDST ASSY, T5, DUAL, W/M-ICOMM/R-SEC CBLS 374120-2000

Item
Number Description Part Numbe
r
NSN Numbe
r
1 CABLE, DUAL, ICOMM, T5, AMP/CONN, NF, MONO 354702-1110
2 CABLE, DUAL, RADIO, T5, NF, PRIMARY 354704-1130
3 CABLE, DUAL, ICOMM, T5, AMP/CONN, NF,
BINAURAL 354702-1220
4 CABLE, DUAL, RADIO, T5, NF, SECONDARY 354704-2130
5 MODULE ASSY, T5, DUAL COMM, SPARE 356190-2000
6 MODULE ASSY, T5, SINGLE COM, MONAURAL,
SPARE 356190-1100
7 MODULE ASSY, T5, SINGLE COM, BINAURAL,
SPARE 356190-1200
8 BOOM MIC ASSY, SPARE 356195-0010
9 WINDSCREEN, BOOM MIC, SPARE 280191-001 5965-01-525-1684
10 NAPEBAND/YOKE ASSY, W/COVER, SPARE 356199-0010
11 NAPEBAND, COVER, SPARE 280187-001 5965-01-525-2019
12 HEADSTRAP KIT, SPARE 277285-001 5965-01-525-1695
13 EAR CUSHION PAIR, SPARE 356202-0010
14 EARCUPS ASSY, T5, SPARE
(WITHOUT NAPE BAND / YOKE ASSEMBLY) 356203-0010
15 CLOTHING CLIP, SPARE 310490-0010
16 BATTERY DOOR, MODULE, SPARE 356205-0010
17 CASE, HEADSET, T5 361424-0010
18 HEADPHONE ASSY,T5,W/NAPEBAND,SPARE 370075-0010
19 MOD ASSY, W/O BOOM MIC, T5, SINGLE,
MONAURAL 370250-1100
20 MOD ASSY, W/O BOOM MIC, T5, SINGLE,
BINAURAL 370250-1200
21 MOD ASSY, W/0 BOOM MIC, T5, DUAL, COMM 370250-2000
22 HEADPHONE ASSY W/NAPEBAND, T5 370075-0010


12
System Configurations

13
System Configurations (continued)

14
277285-001
280191-001
Cables and Replacement Parts

15
DISASSEMBLY PROCEDURES
IMPORTANT NOTE: These products are
RoHS compliant. Use ONLY lead free
solder when making repairs.
1. Boom Microphone Replacement
1.1 Loosen the captive screw that retains
the boom microphone base to the left
earcup.
1.2 Gently pull the base of the boom micro-
phone away from the earcup. Unplug the
boom microphone connector from the wiring
harness.
Note:
Reverse this procedure for installing a
replacement boom microphone.
2. Ear Cushion Replacement
2.1 Insert your fingers at the location
indicated in the photo at left and pull off the
ear cushion from the earcup.
2.2 Remove any residual glue from the
earcup assembly.
2.3 Remove and discard the tape liners
from the replacement ear cushion.

16
DISASSEMBLY PROCEDURES
2.4 Align and press the replacement ear
cushion onto the earcup assembly until it
snaps into place. Ensure it is fully seated.
3. Nape Band Replacement
3.1 Remove nape band cover
3.2 Press upward on nape band yoke until
the yoke pin clears the earcup. Disengage
the lower yoke pin from the earcup. Perform
this step on the other earcup.
3.3 Insert the replacement nape band upper
yoke pin into the earcup upper pin hole.
Press downward on the yoke and engage
the lower yoke pin in the earcup lower pin
hole.
3.4 Replace the nape band cover. Only the
middle portion secures the earcup wire to
the nape band.
Note: The cable running between the
earcups should be on the outer side of the
yoke. Remove and reuse serial number
label on replacement nape band. Attach
new product label to nape band.
4. Earcup Assembly Replacement
Note: The earcup assembly includes both
earcups, the nape band w/cover and the
head strap.
4.1 Remove the two captive screws that
secure the control module cable / boom
microphone to the bottom of the left earcup.
4.2 Gently pull the control module cable /
Yoke pin
Cable on outer side

17
DISASSEMBLY PROCEDURES
boom microphone assembly straight down
and away from the earcup. It should unplug
from the left earcup connector as a unit.
5. Control Module Replacement
Note: The control module is not repairable.
It is a sealed unit. The control module
cables are not replaceable separately
from the control module.
5.1 Loosen the captive screw that secures
the boom microphone assembly to the left
earcup. Gently pull the boom mic assembly
away from the earcup.
Unplug the boom microphone from the
earcup wiring harness.
5.2 Loosen the two captive screws that
secure the control module cable to the
bottom of the left earcup. Gently pull the

18
DISASSEMBLY PROCEDURES
control module cable straight down. It
should unplug from the bottom of the left
earcup.
6. Battery Cover Replacement
6.1 On the control module, loosen the
captive screw that holds the battery door
closed over the batteries. Do not completely
remove the screw.
6.2 On the control module, remove the
screw and nut that secure the battery cover.
Take care to not lose the small nut. It is not
captive to the control module.
Reassembly Note: The small nut should be
re-installed on the same side as the clothing
clip, as shown in the photo at left.
7. Head Strap Assembly Replacement
7.1 Using a T10 Torx head wrench, remove
the screw securing the head strap to the
earcup assembly. Repeat this for the other
earcup.
7.2 Reattach the replacement head strap
using the screw removed in step 7.1.
Note: The replacement head strap comes
as a set. Ensure the strap loops are facing

19
DISASSEMBLY PROCEDURES
outward on each earcup. When worn, the
straps should interlock without twisting.
8. Attachment Clip Replacement /
Relocation
8.1 Remove the screw securing the attach-
ment clip to the control module.
8.2 Align the square alignment holes on the
replacement clip to the alignment feature on
the control module and secure with the
screw removed in step 8.1.
Note: The clip can be installed on either
side of the control module and either
perpendicular or parallel to the cable.

20
Note: The following procedures contain two
separate test procedures.
The first test is for internal Bose®repair
centers that have the required Bose final
audio test system.
The second test procedure is a less complex
light-up-and-play type test for repairs per-
formed in the field.
Internal Bose Repair Center Tests
Equipment Required
The following hardware and software are
needed to perform the tests described
herein. Equivalent hardware may be substi-
tuted.
IMPORTANT NOTE: These products are
RoHS compliant. Use ONLY lead free
solder when making repairs.
Bose Final Audio Test System
This system connects to the headset and
provides all stimulus signals necessary to
excite the headset for listening tests.
The room in which tests are performed must
be within the following range of environmen-
tal conditions:
• Temperature - between 62°F and 82°F
• Humidity - between 10% and 90% R.H.
• Ambient Noise - less than 45 dB(C)SPL
• Noise Signal for noise attenuation listening.
- The test system must produce broad
band noise, 50 Hz to 10 kHz, approxi-
mately pink (third-octave spectrum flat
vs. frequency) below 1 kHz and third-
octave spectrum weighted approximately
inversely with frequency above 1 kHz,
overall level 94 dB SPL ±3 dB. Duration
of 30 minutes or more and must not
repeat more than one time during that
interval.
TEST PROCEDURES
Test Setup
• Install two AA batteries into the control
module for talk through capability.
• Connect the headset to the
intercommunications system
Definitions
Background Noises Noise present in the
absence of other excitation, including the
following:
• Hum Constant low frequency signal,
caused by power line interference.
• Hiss Steady, broad mid-to-high frequency
signal caused by noise of headset electron-
ics.
• Static Intermittent crackling signal, caused
by external electrical interference.
• Whine Sharp continuous signal, caused by
narrow overvoltage pulses on power line.
• Ripple Noises caused by interference on
power supply line at various frequencies.
Instability Noises related to acoustic leaks
or malfunctions compromising stability,
including the following:
• Squeal Mid-to-high frequency variable
tone.
• Motor-boating Lower frequency periodic
noise.
• Buzz Harmonic produced by vibration in
the presence of an audio signal. This noise
is usually related to mechanical faults.
Overload Noises related to movement,
pressure or impact on headset as well as
extremely high external noise, including the
following:
• Click Sharp transient caused by collapse
of driver diaphragm. Generally very notice-
able.
• Thump Low frequency transient, caused
by saturation of headset electronics.
• Pop Low frequency transient, caused by
saturation of ANR loop.