Ericsson 19B801507P2 Maintenance Manual

Mobile Communications

VEHICULAR CHARGER/
REPEATER UNIT
19B801507P2

Printed in U.S.A.

Maintenance Manual

LBI-31869A

DESCRIPTION

General Electric Vehicular Charger/Repeater units pro­vide the charging facility for the portable radio unit and the
Vehicular Repeater System enable/disable function. The
portable radio unit battery pack will be charged as long as
the radio is inserted i nto the charging compartment. The
Vehicular Repeater System is automatically disabled when­ever the portable radio unit is inserted into the charging
compartment. It will recharge either the standard high, or
extra high capacity nickel-cadmium batteries.

The charging contacts are automatically connected
when the radio is inserted into the charger. Radio detect
switch S1, located in the battery compartment, applies power
to the charging circuit when the radio is inserted. A second
switch senses the size of the battery pack and adjusts the
charging rate accordingly.

Heat sensors constantly monitor the temperature of both
the battery pack and the charging insert. When a cold battery
pack is inserted into the charging insert, the charger will wait
until the battery pack has warmed up to within about 10°C
of ambient. The charger will then, automatically, ap pl y t he
high charge rate. When the battery pack overcharges enough
to heat the cells 10°C above ambient, the charger will switch
from fast charge to trickle charge.

The charger also has a memory that is set when the
charger switches from the high charging rate to the trickle
charge rate and is reset when the battery pack is removed
from the charging insert. If a hot battery is in the charging
insert and the memory has not been reset, the charger will
remain at the trickle charge rate. If the memory has been reset
the charger will wait until the battery pack has cooled before
automatically switching to fast charge. If a fully charged
battery pack is removed from the charging insert and then
reinserted, it will charge for about 1/2 hour until the battery
pack reheats.

A voltage cut-off circuit has also been incorporated to
prevent overcharging and "gassing" of the battery pack.
Battery voltage is constantly monitored and, if the battery
pack charge terminal voltage exceeds 9.5 volts, high rate
charge is terminated and the LED READY light is turned on.

If the radio is on when it is in the charger, it is powered
from the radio battery while it is being charged. If the radio
is OFF while it is in the charger, it is inoperative; the battery
is charged if either condition exists.

CONTROLS AND INDICATORS

Four switches and four indicators provide control and
status information for the Vehicular Cha rger. Refer to Figure
1 for location of controls and indicators.

RADIO ENGAGED (RED) Lights when the radio is

inserted properly into the
charger and the radio i s
latched.

CHARGE (red) Indicates the battery is

being charged.

READY (GREEN) Indicates the battery is

fully charged. The
charger will automat­ically switch from a rapid
charge rate to a trickle
charge rate.

REPEATER ON-OFF (yellow) Indicates the repeater is

on.

S1 Radio Detect Closes when the radio is

inserted into the charger.
Applies battery voltage
to Charger Control cir­cuit and Repeater Dis­play board.

S2 Battery Set Resets the power off and

memory circuit.

Copyright © September 1987, General Electric Company

TABLE OF CONTENTS

SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

CIRCUIT ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

CHARGER BOARD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

DISPLAY REP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

DISASSEMBLY PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

ADJUSTMENT PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

TROUBLESHOOTING PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

TEST ADAPTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

LIST OF TABLES

TABLE 1 - QUICK CHECKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

TABLE 2 - EQUIPMENT STATUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

TABLE 3 - VOLTAGE READINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

SPECIFICATIONS*

INPUT POWER 11.1 TO 16.5 Volts

DC, negative ground
CURRENT DRAIN 1.7 A maximum
INPUT CURRENTS

Standby 1 mA maximum

Radio Squelched, Trickle Charge 100 mA maximum

Radio Squelched, Rapid Charge 1700 mA maximum
CHARGE TIME

Standard High Capacity 3 Hours

Extra High Capacity 4 Hours
CHARGE CAPACITY AND TIME VS TEMPERATURE (Standard High Capacity)

Temperature Time Capacity

+5°C (+41°F) 3.3 Hours 100%

+25°C (+77°F) 3.0 Hours 100%

+45°C (+113°F) 2.7 Hours 70%
INDICATORS

Radio Engaged Red

Charge Red

Repeater ON Yellow
DIMENSIONS.(H x W x D) 22.6 x 15 x 7 cm

(8.9 x 5.9 x 2.7 ins.)

WEIGHT 1.4 kG (3.1 lb)

* These specifications are intended primarily for the use of the service technician.

Figure 1 - Veh icular Charge r

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S3 Radio Engaged C loses when r adio i s

properly inserted into
charging insert and ap­plies power to DS1, RA­DIO ENGAGED
indicator.

S1 Repeater OFF-ON ON: Enables Vehicular

Repeater function if ra­dio is not inserted into
charging compartment.

OFF: Vehicular Repeater
System is disabled.

OPERATION

Temperature characteristics of nickel-cadmium batter­ies, prevent a full charge at temperature extremes. For maxi­mum charge, recharge the battery pack at ambient room
temperature or between 65° and 85°F.

CHARGER/REPEATER OPERATION

The following procedures describe the recharging of the
portable radio battery pack and the operation of the Vehicular
Repeater System.

1. The power switch on the radio battery pack may be
in the ON or OFF position.

2. Insert radio unit into charging compartment with its
speaker facing forward (see Figure 2.).

3. Slide the PO SILATCH

TM

toward the portable radio
unit until you feel it engage and the red RADIO
ENGAGED indicator lights.

4. Place the REPEATER ON OFF switch to the ON
position. The red repeater ON indicator will not light
until the portable radio is removed from the charging
compartment.

5. The red CHARGE indicator will light and remain lit
until the portable radio unit is removed or until the
vehicular repeater/charger unit circuits sense that the
battery pack has reached total charge capacity. At this
time the green READY indicator will also light,
indicating that the charger has switched to th e trickle
charge rate.

6. To remove the portable radio from the charging
compartment, depress the blue push-button release
on the POSILATCH and sli de the latch completely
away from the portable radio unit. The red RADIO
ENGAGED indicator will turn off and the portable
radio unit can be removed from the charging com­partment (see Figure 2).

7. Removing the portable radio unit will automat i ca lly
enable the Vehicular Repeater System and the red
REPEATER ON indicator will light.

CIRCUIT ANALYSIS

The Vehicular Charger is comprised of a Charger board,

LED board, Display Repeater board, and a UDC board.

CHARGER BOARD

The Charger board contains the charging circuit, with

voltage and temperature cut-off circuits.

CHARGING CIRCUIT

When power is first applied to the charger, the voltage at
pin 5 of Comparator A7 is higher than at pin 6 of A7 due to the
charging time of C18. The higher voltage causes the output at
pin 7 of A7 to go high, keeping A13 turned off. This allows the
battery to start charging. A block diagram of the Vehicular
Charger is shown in Figure 3.

Charging current flows through series connected resistors
R21 and R22 to regulator transistor Q3. The output of Q3 i s
connected to the positive charging contact of the battery. Test
Point TP2 provides a convenient

place to monitor the positive battery contact. A portion of the
charging current is routed through resistor R24 and transistor
Q2 to turn on CHARGE LED DS3 on the LED board and to
provide a trickle charge when Q2 turns off. The series con­nected charge circuit determines the high charge rate and is
controlled by the temperature controlled cut-off circuit.

CHARGER CONTROL CIRCUIT

The Charger Control circuit consists of a temperature
controlled cut-off circuit and battery charged memory circuit.
The temperature controlled cut-off circuit consists of inte­grated circuit A13, a bridge circuit comprised of R29, R30,
R33, thermistors RT1 and RT (B ATT), and associated circuitry.
Temperature cut-off IC A13 monitors the temperature of the
charging insert through thermistor RT1 and the temperature of
the battery pack through internal thermistor RT (B AT T). It also
controls transistors Q3 and Q4, turns the "READY" indicator
on when the battery pack is fully charged, and provides mem­ory to prevent the same battery pack from being recharged a t
the high rate.

Thermistors RT1 and R T (BATT) are connected with R29,
R30, and R33 to form a bridge circuit (see Figure 4). The output
of the bridge circuit is connected to terminals 13 and 14 of A13.

The General Electric Vehicular Charger is designed
to recharge the GE standard high capacity battery
pack and the extra high capacity battery pack. At­tempting to recharge any other battery pack or bat­teries may result in damage to equipment, leakage,
or explosion.

WARNING

NOTE

The REPEATER OFF-ON switch must be in the
ON position for the Vehicular Repeater System to
function.

NOTE

When the portable radio unit is placed in the charg­ing insert, set the REPEATER OFF-ON switch to
ON so the Vehicular Repeater System will be en­abled automatically when the portable radio is re­moved from the charger.

DO NOT use the antenna to remove the portable
radio from the charging compartment.

CAUTION

NOTE

The Vehicular Repeater System will be disabled as
long as the portable radio unit is in the charging
compartment or the REPEATER OFF-ON switch is
in the OFF position.

Figure 2 - Inserting and Removing Portable Radio Unit

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