Motorola E685 User manual

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CDMA 800MHz
Motorola E685 Service Manual
The World’s Leading Cellular
Telephone Manufacturer

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Preface
Forward
Scope of Manual
This manual is intended for use by experienced technicians familiar with similar
types of equipment. It is intended primarily to support basic servicing, which
consists primarily of mechanical repairs and circuit board replacement. Authorized
distributors may opt to receive additional training to become authorized to perform
limited component repairs. Contact your regional customer Support Manager for
details.
Service
Motorola’s regional Cellular Subscriber Service Centers offer some of the finest
repair capabilities available to Motorola Subscriber equipment users. The Cellular
Subscriber Service Centers are able to perform computerized adjustments and
repair most defective transceivers and boards. Contact your regional Customer
Service Manager for more information about Motorola’s repair capabilities and
policy for in-warranty and out-of-warranty repairs in your region
UIM Card
UIM Card contains your Phone Number, service details, and phonebook and
Message memory.
Do not bend or scratch your UIM Card. Avoid exposing your UIM Card to static
electricity, water, or dirt.

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General Safely Information
Exposure to Radio Frequency Signals
You wireless handheld portable telephone is a low power radio transmitter and receiver.
When it is ON, it receives and also sends out radio frequency (RF) signals .
· International Commission on Non-Ionizing Radiation Protection (ICNIRP) 1996
· Verband Deutscher Elektrotechniker(VDE) DIN-0848
· United States Federal Communications Commission, Radio Frequency Exposure
Guidelines(1996)
· National Radiological Protection Board of the United Kingdom, GS 11, 1988
· American National Standards Institute(ANSI) IEEE. C95. 1-1992
· National Council on Radiation Protection and Measurements(NCRP). Report 86
· Department of Health and Welfare Canada. Safety Code 6
These standards were based on extensive scientific review. For example, over 120
scientists, engineers, and physicians from universities, government health agencies, and
industry reviewed the available body of research to develop the updated ANSI Standard.
The design of your phone complies with these standards when used normally.
Use only the supplied or an approved replacement antenna. Unauthorized antennas,
modifications, or attachment could damage the phone and may violate local agency regulations.
■ Normal Operation
Hold the phone as you world any other telephone, with the antenna pointed up
and over your shoulder.
■ Tips on Efficient Operation:
Observe the following guidelines to operate your phone most efficiency.
- Extend your antenna fully.
- Do not touch the antenna unnecessarily when the phone is in use.
Contact with the antenna affects call quality and may cause the phone to
operate at a higher power level otherwise needed.
Antenna Care
■ Batteries

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CAUTION !
All batteries can cause property damage, injury or burns if a conductive
material, such as jewelry, keys or beaded chains, touches exposed terminals.
The material may complete an electrical circuit and become quite hot. To
protect against such unwanted current drain, exercise car in handing and
charged battery, particularly when placing it inside your pocket, purse or other
container with metal objects.
■ Driving
Check the laws and regulations on the use of wireless telephones in the areas
where you drive. Always obey them. Observe the following guidelines when
using your phone while driving.
Give full attention to driving-driving safely is your first responsibility; Use
hands-free phone operation, if available.
Pull off the road and park before making or answering a call if driving
conditions to require.
Most modern electronic equipment is shielded from RF signals. However,
certain electronic equipment may not be shielded against the RF signals from
your wireless phone.
■ Pacemakers
The Health Industry Manufactures Association recommends that a minimum
separation on six (6″) inches be maintained between a handheld wireless
phone and a pacemaker to avoid potential interference with the pacemaker.
These recommendations are consistent with the independent research by and
recommendations of Wireless Technology Research.
Person with pacemakers:
- Should ALWAYS keep the phone more than six inches from their pacemaker
when the phone is turned ON;
- Should not carry the phone in a breast pocket;
- Should use the ear opposite the pacemaker to minimize the potential for

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interference.
Electronic Devices
- Should turn the phone OFF immediately if you have any reason to suspect that
interference is taking place.
■ Hearing Aids
Some digital wireless phones may interfere with some hearing aids. In the
event of such interference, you may want to consult your hearing aid
manufacture to discuss alternatives.
■ Other medical devices
If you use any other personal medical device, consult the manufacture of your
device to determine if it is adequately shielded from external RF energy. Your
physician may be able to assist you in obtaining this information.
Turn your phone OFF in health care facilities when any regulations posted in
these areas instruct you to do so. Hospitals or health care facilities may be
using equipment that could be sensitive to external RF energy.
■ Vehicles
RF signals may affect improperly installed or inadequately shielded electronic
systems in motor vehicles. Check with the manufacturer of any equipment that
has been added to your vehicle.
■ Posted Facilities
Turn your phone OFF in any facility where posted notices so require.
■ Aircraft
Airline regulations prohibit using your phone while in the air.
Switch OFF your phone before boarding an aircraft.
■ Blasting Areas
To avoid interfering with blasting operations, turn your phone off when in a
“blasting area” or in areas posted: “Turn off two-way radio”. Obey all signs
and instructions.

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■ Potentially Explosive Atmospheres
Turn your phone off when in any area with a potentially explosive atmosphere,
and obey all signs and instruction. Sparks in such areas could cause an
explosion or fire resulting in bodily injury or even death.
Areas with a potentially explosive atmosphere are often, but not always, clearly
marked. The include fueling areas such as gasoline station; below deck on
boats, fuel or chemical transfer or storage facilities; vehicles using liquefied
petroleum has (such as propane or butane); area where the air contains
chemicals or particles, such as grain, dust, or metal powders; and any other
area where you would normally be advised to turn off your vehicle engine.
■ For Vehicles Equipped with an Air Bag
An air bag inflates with great force. DO NOT place objects, including both
installed or portable wireless equipment, in the area over the bag or in the air
bag deployment area. If in-vehicle wireless equipment is improperly installed
and the air bag inflates, serious injury could result.

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Service Guide
■ Adjust the cellular phone in the shield box or shield room shielded from the
ambient spurious/noise for a precise adjustment.
■ Note that magnetism of the magnetic tools may cause malfunction of the mai
parts(lcs) of the cellular phone.
■ Use a thick wire to measure the RF level. A thick wire has less RF resistance
and may lessen the error margin of the measurement.
■ Be sure to use the standardized driver to disassemble the cellular phone set.
■ Avoid repairing with the power switch on after connecting the test pack. It may
cause short circuit by over-current and part deterioration.
■ Note that overheating of the soldering iron may displace the PCB land during
the board repair.
■ Any addition of separate devices to the product that may change the
performance of the product is not allowed, as specified in the product type
registration.
■ The contents of the service manual and functions of the cellular phone are
subject to change.

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Description
Cellular System Overview
NOTE
The following description is intended only as a preliminary general introduction to
cellular systems. This description is greatly simplified and does not illustrate the
full operation capabilities, techniques, or technology involved in cellular systems.

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Overall Concept
Cellular systems are used to provide radiotelephone service in the frequency range
of 826 – 891 MHz.
A cellular system provides higher call handling capacity and system availability
than would be possible with conventional radiotelephone systems that require total
system area coverage on every operating channel. The cellular system divides the
system coverage area into several adjoining sub-areas, or cells.
Each cell contains a base station (cell site) which provides transmitting and
receiving facilities. CDMA is a “spread spectrum”technology, which means that it
spreads the information contained in a particular signal of interest over a greater
bandwidth than the original signal.
With CDMA, unique digital codes, rather than separate RF frequencies or channels
are used to differentiate subscribers, The codes are shared by both the mobile
station and base station and are called “pseudo-random code sequences”. Since
CDMA is a spread spectrum technology, all users share a range of the radio
spectrum.
CDMA cell coverage is dependent upon the way the network is designed. For each
system 3 characteristics must be considered, coverage, quality, and capacity.
There 3 must be balanced for desired lever of performance.

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Some of the CDMA benefits are:
■ Improved call quality with better and more consistent sound.
■ Enhanced privacy.
■ Variable rate vocoder.
Figure1: Hypothetical Cell System
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CELL A
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CELL B
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CELL C
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CELL D
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