Motorola Gp640 Gp680 Basic 68p64115b23a Manual

							Chapter 2
INTRINSICALLY SAFE RADIO INFORMATION
1.0 FMRC Approved Equipment
Anyone intending to use a radio in a location where hazardous concentrations of flammable material
exist (hazardous atmosphere) is advised to become familiar with the subject of intrinsic safety and
with the National Electric Code NFPA 70 (National Fire Protection Association) Article 500
(hazardous [classified] locations).
An Approval Guide, issued by Factory Mutual Research Corporation (FMRC), lists manufacturers
and the products approved by FMRC for use in such locations. FMRC has also issued a voluntary
approval standard for repair service (“Class Number 3605”).
FMRC Approval labels are attached to the radio to identify the unit as being FM
Approved for specified hazardous atmospheres. This label specifies the hazardous
Class/Division/Group along with the part number of the battery that must be used.
Depending on the design of the portable unit, this FM label can be found on the
back of the radio housing or the bottom of the radio housing.Their Approval mark is shown below.
Radios must ship from the Motorola manufacturing facility with the hazardous atmosphere capability
and FM Approval labeling. Radios will not be“upgraded”to this capability and labeled in the field.
A modification changes the unit’s hardware from its original design configuration. Modifications can
only be done by the original product manufacturer at one of its FMRC audited manufacturing
facilities.
Unauthorized or incorrect modification of an FMRC Approved Product unit will negate the Approval
rating of the product.
WARNING: Do not operate radio communications equipment in a hazardous atmosphere
unless it is a type especially qualified (e.g. FMRC Approved) for such use. An explosion or
fire may result.
WARNING: Do not operate the FMRC Approved Product in a hazardous atmosphere if it has
been physically damaged (e.g. cracked housing). An explosion or fire may result.
WARNING: Do not replace or charge batteries in a hazardous atmosphere. Contact sparking
may occur while installing or removing batteries and cause an explosion or fire.
WARNING: Do not replace or change accessories in a hazardous atmosphere. Contact
sparking may occur while installing or removing accessories and cause an explosion or fire.
WARNING: Do not operate the FMRC Approved Product unit in a hazardous location with the
accessory contacts exposed. Keep the connector cover in place when accessories are not
used.
WARNING: Turn radio off before removing or installing a battery or accessory.
WARNING: Do not disassemble the FMRC Approved Product unit in any way that exposes
the internal electrical circuits of the unit.
WARNING: Failure to use an FMRC Approved Product unit with an FMRC Approved battery
or FMRC Approved accessories specifically approved for that product may result in the
dangerously unsafe condition of an unapproved radio combination being used in a
hazardous location.
FM
APPROVED
!
! 
						

							2-2 INTRINSICALLY SAFE RADIO INFORMATION
2.0 Repair of FMRC Approved Products
REPAIRS FOR MOTOROLA FMRC APPROVED PRODUCTS ARE THE RESPONSIBILITY OF
THE USER
You should not repair or relabel any Motorola manufactured communication equipment bearing the
FMRC Approval label (“FMRC Approved Product”) unless you are familiar with the current FMRC
Approval standard for repairs and service (“Class Number 3605).
You may want to consider using a repair facility that operates under 3605 repair service approval.
FMRC’s Approval Standard Class Number 3605 is subject to change at any time without notice to
you, so you may want to obtain a current copy of 3605 from FMRC. Per the December, 1994
publication of 3605, some key definitions and service requirements are as follows:
2.1 Repair
A repair constitutes something done internally to the unit that would bring it back to its original
condition Approved by FMRC. A repair should be done in an FMRC Approved facility.
Items not considered as repairs are those in which an action is performed on a unit which does not
require the outer casing of the unit to be opened in a manner which exposes the internal electrical
circuits of the unit. You do not have to be an FMRC Approved Repair Facility to perform these
actions.
2.2 Relabelling
The repair facility shall have a method by which the replacement of FMRC Approval labels are
controlled to ensure that any relabelling is limited to units that were originally shipped from the
Manufacturer with an FM Approval label in place. FMRC Approval labels shall not be stocked by the
repair facility. An FMRC Approval label shall be ordered from the original manufacturer as needed to
repair a specific unit. Replacement labels may be obtained and applied by the repair facility
providing satisfactory evidence that the unit being relabelled was originally an FMRC Approved unit.
Verification may include, but is not limited to: a unit with a damaged Approval label, a unit with a
defective housing displaying an Approval label, or a customer invoice indicating the serial number of
the unit and purchase of an FMRC Approved model.
WARNING: Incorrect repair or relabeling of any FMRC Approved Product unit could
adversely affect the Approval rating of the unit.
WARNING: Use of a radio that is not intrinsically safe in a hazardous atmosphere could
result in serious injury or death.
! 
						

							Repair of FMRC Approved Products2-3
2.3 Do Not Substitute Options or Accessories
The Motorola communications equipment certified by Factory Mutual is tested as a system and
consists of the FM Approved portable, FM Approved battery, and FM Approved accessories or
options, or both. This Approved portable and battery combination must be strictly observed. There
must be no substitution of items, even if the substitute has been previously Approved with a different
Motorola communications equipment unit. Approved configurations are listed in the FM Approval
guide published by FMRC, or in the product FM Supplement. This FM Supplement is shipped with
FM Approved radio and battery combination from the manufacturer. The Approval guide, or the
Approval standard Class Number 3605 document for repairs and service, can be ordered directly
through Factory Mutual Research Corporation located in Norwood, Massachusetts. 
						

							2-4 INTRINSICALLY SAFE RADIO INFORMATION 
						

							Chapter 3
MAINTENANCE
1.0 Introduction
This chapter provides details about the following:

Preventive maintenance (inspection and cleaning)

Safe handling of CMOS and LDMOS devices

Disassembly and reassembly of the radio

Repair procedures and techniques

Installation of Option Boards
2.0 Preventive Maintenance
The radios do not require a scheduled preventive maintenance program; however, periodic visual
inspection and cleaning is recommended.
2.1 Inspection
Check that the external surfaces of the radio are clean, and that all external controls and switches
are functional. It is not recommended to inspect the interior electronic circuitry.
2.2 Cleaning Procedures
The following procedures describe the recommended cleaning agents and the methods to be used
when cleaning the external and internal surfaces of the radio. External surfaces include the front
cover, housing assembly and battery case. These surfaces should be cleaned whenever a periodic
visual inspection reveals the presence of smudges, grease, and/or grime.
The only recommended agent for cleaning the external radio surfaces is a 0.5% solution of a mild
dishwashing detergent in water. The only factory recommended liquid for cleaning the printed circuit
boards and their components is isopropyl alcohol (70% by volume).
Cleaning External Plastic Surfaces
Apply the 0.5% detergent-water solution sparingly with a stiff, non-metallic, shor t-bristled brush to
work all loose dirt away from the radio. Use a soft, absorbent, lintless cloth or tissue to remove the
solution and dry the radio. Make sure that no water remains entrapped near the connectors, cracks,
or crevices.
NOTEInternal surfaces should be cleaned only when the radio is disassembled for service
or repair.
CAUTION: The effects of certain chemicals and their vapors can have harmful results on certain
plastics. Avoid using aerosol sprays, tuner cleaners, and other chemicals.! 
						

							3-2MAINTENANCE
Cleaning Internal Circuit Boards and Components
Isopropyl alcohol (70%) may be applied with a stiff, non-metallic, short-bristled brush to dislodge
embedded or caked materials located in hard-to-reach areas. The brush stroke should direct the
dislodged material out and away from the inside of the radio. Make sure that controls or tunable
components are not soaked with alcohol. Do not use high-pressure air to hasten the drying process
since this could cause the liquid to collect in unwanted places. After completing of the cleaning
process, use a soft, absorbent, lintless cloth to dry the area. Do not brush or apply any isopropyl
alcohol to the frame, front cover, or back cover.
3.0 Safe Handling of CMOS and LDMOS Devices
Complementary metal-oxide semiconductor (CMOS) devices are used in this family of radios, and
are susceptible to damage by electrostatic or high voltage charges. Damage can be latent, resulting
in failures occurring weeks or months later. Therefore, special precautions must be taken to prevent
device damage during disassembly, troubleshooting, and repair.
Handling precautions are mandatory for CMOS circuits and are especially impor tant in low humidity
conditions. DO NOT attempt to disassemble the radio without first referring to the following
CAUTION statement.
NOTEAlways use a fresh supply of alcohol and a clean container to prevent contamination by
dissolved material (from previous usage).
CAUTION: This radio contains static-sensitive devices. Do not open the radio unless you are properly
grounded. Take the following precautions when working on this unit:


Store and transpor t all CMOS devices in conductive material so that all exposed
leads are shorted together. Do not insert CMOS devices into conventional plastic
“snow”trays used for storage and transportation of other semiconductor devices.

Ground the working surface of the service bench to protect the CMOS device. We
recommend using the Motorola Static Protection Assembly (part number
0180386A82), which includes a wrist strap, two ground cords, a table mat, and a
floor mat.

Wear a conductive wrist strap in series with a 100k resistor to ground. (Replacement
wrist straps that connect to the bench top covering are Motorola par t number RSX-
4015.)

Do not wear nylon clothing while handling CMOS devices.

Do not insert or remove CMOS devices with power applied. Check all power
supplies used for testing CMOS devices to be certain that there are no voltage
transients present.

When straightening CMOS pins, provide ground straps for the apparatus used.

When soldering, use a grounded soldering iron.

If at all possible, handle CMOS devices by the package and not by the leads. Prior to
touching the unit, touch an electrical ground to remove any static charge that you
may have accumulated. The package and substrate may be electrically common. If
so, the reaction of a discharge to the case would cause the same damage as
touching the leads.
! 
						

							Repair Procedures and Techniques—General 3-3
4.0 Repair Procedures and Techniques — General
Parts Replacement and Substitution
When damaged parts are replaced, identical parts should be used. If the identical replacement part
is not locally available, check the parts list for the proper Motorola part number and order the part
from the nearest Motorola Communications parts center listed in the“Piece Parts”section of this
manual.
Rigid Circuit Boards
This family of radios uses bonded, multi-layer, printed circuit boards. Since the inner layers are not
accessible, some special considerations are required when soldering and unsoldering components.
The printed-through holes may interconnect multiple layers of the printed circuit. Therefore, exercise
care to avoid pulling the plated circuit out of the hole.
When soldering near the 20-pin and 40-pin connectors:

Avoid accidentally getting solder in the connector.

Be careful not to form solder bridges between the connector pins.

Examine your work closely for shorts due to solder bridges.
Flexible Circuits
The flexible circuits are made from a different material than the rigid boards, and require different
soldering techniques. Excessive prolonged heat on a flexible circuit can damage the material.
Therefore, avoid excessive heat and excessive bending.
For parts replacement, use the ST-1087 Temperature-Controlled Solder Station with a 600-700
degree tip, and use small diameter solder such as ST-633. The smaller size solder will melt faster
and require less heat to be applied to the circuit.
To replace a component on a flexible circuit:
1.Grasp with seizers (hemostats) the edge of the flexible circuit near the part to be removed.
2.Pull gently.
3.Apply the tip of the soldering iron to the component connections while pulling with the seizers.
5.0 Disassembling and Reassembling the Radio — General
Since these radios may be disassembled and reassembled with the use of only four (board to
casting) screws, it is important to pay particular attention to the snaps and tabs, and how parts align
with each other.
The following tools are required for disassembling the radio:

Small flat blade screwdriver

penknife-size screwdriver

TORX™T6 screwdriver
NOTEDo not attempt to puddle-out components. Prolonged application of heat may damage the
flexible circuit. 
						

							3-4MAINTENANCE
If a unit requires more complete testing or service than is customarily performed at the basic level,
send this unit to a Motorola Authorized Service Center. (See Chapter 1 for a list of authorized
service centers.)
The following disassembly procedures should be performed only if necessary:
Chassis Assembly Disassembly (Paragraph 6.2)
Keypad, Display, and Keypad/Option Board Disassembly (Paragraph 6.3)
Speaker, Microphone, and Universal Connector Flex Disassembly (Paragraph 6.4)
PTT Disassembly (Paragraph 6.5)
Control Top Disassembly (Paragraph 6.6)
6.0 Radio Disassembly — Detailed
6.1 Front Cover from Chassis Disassembly
1.Turn off the radio.
2.Remove the battery:
a. Pull down on the two battery-release buttons.
b. With the buttons pulled down, the top of the battery will fall from the radio.
c. Remove the battery from the radio.
3.Remove the antenna.Figure 3-1Battery Removal
Battery Release
Buttons 
						

							Radio Disassembly—Detailed3-5
4.Pull the volume and channel selector knobs off of their shafts.
5.Separate the chassis from the internal electronics front cover assembly as follows:
a. Insert a small, flat-blade screwdriver, or similar instrument, in between the thin retaining
wall and the chassis at the bottom of the radio. Do not mar the O-ring sealing area on the
housing.
b. Slowly pry the bottom of the chassis from the cover by pushing the small flat-blade
screwdriver down, and rotating the handle of the tool over and behind the base of the
radio. This prying action forces the thin inner plastic wall toward the base of the radio,
releasing the two chassis base tabs.Figure 3-2Knob Removal
NOTEBoth knobs slide on and off. However, they are supposed to fit very tightly on their shafts.
Figure 3-3Chassis Removal
CAUTION: Marring the front cover O-ring sealing area will prevent the radio from sealing properly.
NOTE
Flexible ribbon circuits (flexes) connecting the front cover assembly and the chassis pre-
vent you from completely separating the two units. Display radios and radios with option
boards have two flexes.
Knobs
Radio Chassis
! 
						

							3-6MAINTENANCE
6.Lay the chassis down. Rotate the front cover backward and slightly away from the chassis.
7.Lift the latches on the main circuit board to release the flexes from their connectors.
6.2 Chassis Assembly Disassembly
Use a TORX™screwdriver with a T6 head to remove the four screws holding the main boardto the
chassis.
1.Lift the main board from the chassis (See Figure 3-5).
2.Remove the four small O-ring retainers from their slots in the chassis. Note the alignment of
the retainers for reassembly.Figure 3-4Unlatch Flex Connectors
Figure 3-5Remove Main Board from Chassis
CAUTION: Refer to the CMOS CAUTION paragraph on page 2 before removing the main board. Be sure
to use ESD protection when handling circuit boards.
Latches
Flex Connectors
Main Board
Compliant
Ground
Contact
O-ring
Retaining
FeaturesRadio Chas
s
!