JRC JHS-7 - User manual

INSTRUCTIONINSTRUCTION
MANUALMANUAL
JHSJHS-7
150MHz/1W, TWO-WAY RADIOTELEPHONE APPARATUS/150MHz/1W, TWO-WAY RADIOTELEPHONE APPARATUS/
ON-BOARD COMMUNICATION EQUIPMENTON-BOARD COMMUNICATION EQUIPMENT
ISO 9001, ISO 14001 Certified
SEP. 2018 Edition 1CODE No.7ZPJD0669A
Not use the asbestos
For further information,contact:
URL Head office : http://www.jrc.co.jp/eng/
Marine Service Department
1-7-32 Tatsumi, Koto-ku, Tokyo 135-0053, Japan
: [email protected]
:
[phone]
e-mail
One-call

:$51,1*
䖃Refrain from any of the actions below in handling the primary battery (NBB-389) or the
secondary battery (NBB-248/248A) for this transceiver. Mishandling will cause the risk of
heat generation, burst or electrolyte leakage.
䞉DO NOT heat or dispose of in fire
䞉DO NOT disassemble or modify.
䞉DO NOT short-circuit the ”+” and “-” terminals.
䞉DO NOT charge the primary battery NBB-389
䖃DO NOT use this transceiver in hazardous areas subject to the presence of explosive gases.
&$87,21
䖃To charge the secondary battery (NBB-248/248A), use the dedicated battery charger (NBA-
4141/NBA-4141A).
䖃Charge the battery only in the normal temperature range (0 to 40䉝). Avoid charging it
especially at the temperatures below 0Υ, as this may cause gases development in the
battery to operate safety vent.
䖃To ensure long-life performance of the battery, follow the instructions below:
䞉When have finished charging, disconnect the battery from the charger to store.
Recharge the battery at approximately three month interval even if not used.
䞉Keep the battery in a dry place with little temperature change. Storage in a place with
high temperature, high humid and/or direct sunlight will cause serious deterioration
of the battery performance.
䞉Do not leave the battery in the charger for storage(trickle charging). Trickle charging
will not cause overcharging, however, will cause deterioration of the battery
performance.
䞉Turn off the power switch of the transceiver after using. Overdischarge of the battery
(6V or lower) will cause serious deterioration of the battery performance.
䖃Return unusable secondary batteries to a nearest JRC branch, sales office or dealer.
䖃Charge the secondary battery (NBB-248/248A) before using the transceiver at the first time
to revive the reduced capacity during transportation.
䖃Do not try to disconnect the antenna. If antenna disconnection is under necessity, consult a
nearest JRC branch, sales office or dealer. Antenna disconnection without using dedicated
tool will cause damage of the antenna and/or the transceiver.
Cautions for Use
7ZPJD0669A

Handling of NBB-389 Lithium Primary Battery
WARNING
 Follow the instruction below:
・DO NOT short-circuit the terminals.
・DO NOT heat or dispose of in fire.
・DO NOT disassemble or DO NOT modify.
・DO NOT puncture or DO NOT deform
Mishandling can cause explosion, over-
heating or leakage of strong alkaline
electrolyte solution.
CAUTION
 Since the battery is equipped with a non-
replaceable seal to indicate that it has not
been used, do not detach the seal excluding
emergency situation.
 Check the expiry date regularly. The shelf life
of this battery is five years.
 Contact to nearest JRC branch office or JRC
agent to transport, replace and dispose.
1. General
The Two-way radiotelephone apparatus, JHS-
7/7E/14, installed on or after 23 Nov. 1996 must be
provided with NBB-389 Lithium Primary Battery
for use in the event of a distress situation in
accordance with “IMO Res. A809 (19)”
2. Handling
- The NBB-389 is the primary battery for the
emergency use only. Therefore, usually keep
this battery without mounting it on the
radiotelephone.
- For using the primary battery NBB-389 in an
emergency situation, detach the non-
replaceable seal and mount the primary
battery on the radiotelephone. The mounting
method for the primary battery is the same as
the secondary battery of the NBB-248/248A.
(Refer to instruction manual, subclause 3.3)
3. Expiry date and Maintenance
The shelf life of the primary battery is five years.
Check the expiry date regularly and if required,
replace it before becoming invalid. The expiry date
is indicated on the side of the primary battery.
When exchanging the primary battery,
Contact to nearest JRC branch office or JRC agent.
4. Specifications
Nominal voltage: 9V
Nominal capacity: 4800mAH
Battery type: Lithium-Manganese
Dioxide Battery
Shelf life: 5 years or more
Battery case colour: Yellow
Non-replaceable seal: Equipped (Orange colour)
Weight: Approx.220g

Handling of the carrying strap
The JHS-7 radiotelephone is provided with the shoulder and/or neck carrying strap. For
fixing the strap to the radiotelephone, two fittings on the upper part as shown below are
available.
Additionally the strap includes the weak links to prevent the bearer from being ensnared.
It means that, for example, while grasping the strap if dropped the radiotelephone, the
weak links keep linking, but if hanging by neck accidentally, the weak links are unlinked
for safety.
Static Weight Limit of the weak link: 63.7～117.6 N(6.5～12.0 kgf)
NOTICE)
- DO NOT unlink the weak links of the strap in the unnecessary situation to avoid
the malfunction.
- Always check whether the weak links are covered with rust or not.
- If any rust is found on the weak links, replace the strap with the new one.

I
CAUTION
1. To charge the secondary battery (NBB-248/248A), use the dedicated
battery charger (NBA-4141/NBA-4141A).
2. Charge the secondary battery (NBB-248/248A) before using the
transceiver at the first time to revive the reduced capacity during
transportation. The charging method is described in Chapter 4.
3. The ambient temperature should be between 0℃and 40℃when the
secondary battery is charged. Avoid charging it especially at an
ambient temperature below 0℃.
4. When the secondary battery is out of use, bring it to a nearby JRC
sales office, branch, or dealer.
5. The antenna is firmly assembled with the radiotelephone. Any
attempt to forcibly remove the antenna will cause damage to the
antenna or the equipment. If necessary to remove it, contact a
nearest JRC dealer or branch.
6. Usable channels of the JHS-7 for JG Flag are restricted to three
channels as CH15, CH16 and CH17.
7. When any non-programmed channel is selected, internal speaker
makes buzz for prevention of misoperation.

II
TABLE OF CONTENTS
1. GENERAL····································· 1
1.1 General ································ 1
1.2 Features······························· 1
1.3 Composition ·························· 1
1.3.1 Standard Components ··········· 1
1.3.2 Option ······························· 1
1.3.3
Optional channel programming ··· 1
2. SPECIFICATIONS ·························· 2
2.1 General ································ 2
2.2 Transmitter ·························· 2
2.3 Receiver ······························· 2
3. OPERATION·································· 3
3.1 Description ··························· 3
3.2 Operating Procedure ··············· 4
3.2.1 Preparation························· 4
3.2.2 Call ··································· 4
3.2.3 Closing down······················· 5
3.3
Replacement of Battery Pack
NBB-248/248A and NBB-389 ···· 5
3.4 Handling of Battery Charger
NBA-4141/NBA4141A(Optional) 6
3.4.1 Installation························· 6
3.4.2 Replacement of Fuse ············· 7
3.4.3
Change of Power Supply Voltage ····· 7
3.4.4
Parallel Wiring of Power Cables ····· 7
3.5 Handling of the Accessories······ 8
3.5.1 Carrying Strap ···················· 8
3.5.2 Belt Clip ···························· 8
3.5.3
Connecting of the Earphone and
External Speaker/Microphone ···· 8
3.5.4 Lithium Primary Battery······· 8
4. BATTERY CHARGING····················· 9
4.1 Period of time to charge··········· 9
4.2 Precautions on Charging·········· 9
4.3 Charging Procedure ················ 9
5. MAINTENANCE AND INSPECTION ·10
5.1 Daily Maintenance ················10
5.2 Regular Inspection ················10
6. TROUBLESHOOTING ····················11
6.1 Precautions ··························11
6.2 Troubleshooting Guide············11
6.3 Simple Adjustment ··············· 12
6.3.1 Checking of Voltages ··········· 12
6.3.2
Adjustment of the Synthesizer ··· 12
6.3.3 Frequency Adjustment········· 12
6.3.4 Transmit output Adjustment· 12
6.3.5 Tuning of the Receiver········· 12
7. OPTIONS ···································· 13
7.1 Battery Charger
NBA-4141/NBA4141A ··········· 13
7.2
Primary Battery Pack NBB-389 ·· 13
7.3 Battery Pack NBB-248 ·········· 13
7.4 Battery Pack NBB-248A ········ 13
7.5 Earphone 6UMJD00004 ········· 13
7.6 External Speaker/Microphone
6UMJD00029······················· 13
7.7 Carrying Case MPXP02368····· 13
Appended Drawings
Block Diagram
Outline Drawing
Appended Drawing (Optional)
NBA-4141/NBA-4141A
Battery Charger Outline Drawing
6UMJD00004 Earphone Outline Drawing
6UMJD00029 External Speaker/Microphone
Outline Drawing

1
1. GENERAL
1.1 General
This equipment is designed and manufactured for
two-way communication between survival crafts,
between survival craft and main ship, and between
main ship and a rescue boat in accordance with the
Safety of Life at Sea convention (SOLAS).
This is 150MHz/1W portable radiotelephone which
is capable of installing 13(thirteen) operating
channels for international marine mobile service,
also can be used as on-board communication
equipment.
1.2 Features
(1) Watertightness
This radio telephone is of the watertight structure
to a depth of one meter.
(2) Thirteen operating channels
13(Thirteen) single-frequency voice channels are
provided including channel 16 for safety which
can also be selected easily by an independent
switch.
How ever, usable channels of the JHS-7 for JG
Flag are restricted to CH15, CH16, and CH17.
(3) Easy handling
Controls and switches are designed and located
for easy operation, and can be manipulated even
when thick gloves are worn.
(4) Small size and light weight
This radio telephone is designed in compact with
dimensions of 64mm(width)×165mm(height)×
45.5mm(depth), and weight approximately 600g,
including Battery Pack. And its shape is designed
to facilitate carrying by hand for a long period of
time. Moreover, carrying strap and a belt clip
come with it for easy carrying.
(5) Low power consumption
Since its power consumption is extremely low,
this radio telephone can operate for a long time
(more than 8 hours with transmission reception
and stand-by in the ratio of 1 to1 to 8) once the
battery is charged.
(6) Frequency synthesizer
The use of a frequency synthesizer assures high
frequency stability for all the channels.
(7) Display of transmitting condition
The Tx lamp indicates whether transmitting
output is on or off.
During press-to-talk operation, the Tx lamp lights
up by monitoring carrier level to indicate that
signals are being transmitted.
(8) Charge lamp
When the battery energy is almost consumed, the
BUSY lamp blinks for indicating necessity of the
battery charging.
(9) High reliability
Surface-mounting type ICs, transistors, resistors,
and capacitors, which are suitable for automatic
mounting, assure homogeneous quality and high
stability.
(10) Removable battery pack
The battery pack can be easily replaced because
of its easy removal from the radiotelephone. The
battery pack mounting assembly is protected so
that battery pack can be replaced even under a
rain fall.
Quick charging (within three hours) can be done
by inserting the battery pack into the optional
battery charger NBA-4141/NBA-4141A.
(11) Carrying strap
The strap includes the weak links to prevent the
bearer from being ensnared. It means that, for
example, while grasping the strap if dropped the
radiotelephone, the weak links keep linking, but
if hanging by neck accidentally, the weak links
are unlinked for safety.
Static weight limit: 63.7 ～ 117.6 N (6.5 ～ 12.0 kgf)
1.3 Composition
1.3.1 Standard Components
Item Model Qty Remarks
Radiotelephone JHS-7 1 Inc. antenna
Primary battery NBB-389 1 For emergency only
Secondary battery NBB-248/248A 1 For daily use
Carrying strap MPXP33444 1
Instruction manual 1
Test data 1
1.3.2 Option
Item Model Remarks
Battery charger NBA-4141
/NBA4141A
Primary battery NBB-389 For emergency only
Secondary battery NBB-248/248A For daily use
Ear phone 6UMJD00004
External SP/MIC 6UMJD00029
Carrying case MPXP02368
1.3.3 Optional channel programming
According to custom order, your JHS-7 with upto 7
optional channels will be shipped from JRC factory.
Please designate required channel Nos from simplex
voice channels specified in Appendix 18 of the Radio
Regulation.
Note: The JHS-7 for JG Flag is equipped with no
optional channel.

2
2. SPECIFICATIONS
2.1 General
(1) Operating channels: CH16 （156.800MHz）
CH6 （156.300MHz）
CH13 （156.650MHz）
CH15 （156.750MHz）
CH17 （156.850MHz）
CH67 （156.375MHz）
Note: Usable channels of the JHS-7 for JG flag
are restricted to CH15, CH16, and CH17.
(2) Optional channels: Seven simplex
Channels
selectable from a
range of 156.300 to
156.875MHz
(3) Communication mode: Simplex
(4) Type of emission: G3E/F3E
(5) Antenna: Vertical, non-directional
type (nominal 50Ω)
Gain -3dB
(6) Continuous operation:
More than 8 hours in a duty cycle of 6
seconds of transmission, 6 seconds of
reception and 48 seconds of stand-by.
(7) Power source: Primary battery
(9.0VDC, 4800mAH)
Secondary battery
(7.2VDC, 1000mAH)
(8) Warm-up time: Less than 5 seconds
(9) CH switching period: Less than 5 seconds
(10) Tx/Rx switching period: Within 0.3 seconds
(11) Operating temp range: －20℃to ＋55℃
(12) Storage temp range: －30℃to ＋70℃
(13) Humidity: 93％at 40℃
(14) Safety distance from standard
magnetic compass: 0.4m
(15) Safety distance from steering
magnetic compass: 0.4m
(16) Shock resistance:
No troubles after a fall on the hard wood
floor from a height of 1m.
(17) Vibration resistance:
No troubles after vibrations, up and down,
right and left, and back and forth for
15min. under each of the following
conditions:
60 to 750times/min., full amplitude of
3.2mm;750 to 1500 times/min., full
amplitude of 0.76mm; and 1500 to 3000
times/min., hull amplitude of 0.2mm
(18) Water-tightness:
Operates normally after it is immersed in
water to the depth of one meter for 5 min.
(19) Overall dimensions: 64(W)×165(H)×45.5
(D) mm
(Exc. projections)
(20) Weight: Approx. 600g
2.2 Transmitter
(1) Carrier output power: 0.8W
(2)
Effective radiated power : More than 0.25W
(3) Oscillation: Freq synthesizer
(4) Modulation: Variable reactance
frequency modulation
(5) Frequency stability: Within 10×10－6
(6) Pre-emphasis: 6dB per octave
(7) Modulation frequency: 300 to 3000Hz
(8) Splatter filter: 40log(f/3), f=3 to
15kHz
(9) Occupied bandwidth: Within 16kHz
(10) Max FRQ deviation: Within ±5kHz
(11) Distortion: 10％or less, standard
modulation
(12) Mod input impedance: 600Ω
2.3 Receiver
(1) Receiving system:
Double superheterodyne
1st IF: 21.7MHz
2nd IF: 455kHz
(2) Max usable sensitivity: 6dBμor less,
S+N+D/N ratio of
20dB
(3) Selectivity: 6dB bandwidth :
12kHz or more
70dB bandwidth:
25kHz or less
(4) Spurious response: 70dB or more
(5) Local FRQ variation: 0.001% or less
(6) Blocking: 90dBμor more
(7) Intermodulation: 70dB or more
(8) De-emphasis: 6dB per octave
(9) Rated AF output power: 200mW or more (with
distortion rate of 10％)
(10) Distortion: 10％or less
(11) Squelch sensitivity: Not more than
maximum usable
sensitivity level, and
not exceeds +30dBμ.
(12) Speaker impedance: 8Ω

3
3. OPERATION
3.1 Description
(1) Helical antenna
The flexible helical antenna is firmly assembled
with this radiotelephone. To remove the
antenna, exclusive wrench is required.
(2) Shoulder belt fittings
Fasten the attached shoulder belt to these
fittings before using the belt to carry the
radiotelephone.
(3) PTT(press-to-talk)button
Depressing the switch enables transmission,
and releasing it enables reception.
(4) Speaker
Produces received sounds.
(5) MIC (microphone)
Talk to the microphone during calling.
(6) PUSH button
Press this button to unlock the battery pack
when removing it.
(7) Battery pack NBB-248/248A/389
Supplies power to the radiotelephone. Section
3.3 describes how to replace the battery pack.
(8) Belt clip
Hold the radiotelephone with a belt.
(9) RMT(remote terminal) connector
Connect the optional earphone 6UMJD00004 or
external speaker/microphone 6UMJD00029.
During connecting here, the internal speaker is
automatically tuned off. Also when the external
speaker/microphone is connected, both the
internal speaker and microphone are turned
off. The pin assignments are as follows;
No. Name Function
1 E Ground of the radiotelephone.
2 EXT
PTT
Control line for external control
of PTT. Grounding it enables
transmission.
3 EXT
MIC
Input terminal for the external
microphone. It also outputs a bias
voltage for a condenser microphone.
4 EAR
A
F output (8Ω) for the earphone
and external speaker.
5 MIC
CONT
Control line for control of the
external microphone.
Grounding this terminal turns off
the internal microphone.
6 SP
CONT
Control line for control of the
internal speaker output.
Grounding this terminal turns off
the internal speaker.
Figure 3-1 Appearance
Figure 3-2 Operation Panel

4
(10) Tx lamp
Lights red during press-to-talk operation.
It monitors the transmission output. If the Tx
lamp does not light even when the PTT button
is depressed, the transmission circuit may be
faulty.
(11) PWR/VOL (power switch/volume) control
Works as power switch and volume control.
Turning the PWR/VOL control fully
counterclockwise turns off the power. Turning it
clockwise turns on the power. Sound volume
increases as it is turned clockwise.
(12) BUSY lamp
Lights green while the squelch is open. It also
monitors the battery condition. When the
battery is almost consumed, the BUSY lamp
blinks for warning.
(13) 16(CH16 indicator)
Lights orange when CH16 is selected. This
lamp also monitors the condition of the internal
frequency synthesizer. The 16 indicator blinks
if the frequency synthesizer has any trouble
(unlocking).
(14) CH16 switch
A toggle switch for CH16. Setting it to the 16
position selects CH16. Setting it to the CH
position selects the channel number specified in
the following subparagraph (16).
(15) Background illumination for a channel
number
Illuminates to enable easy reading of the
channel number selected the following
subparagraph (16).
(16) Channel setting switch
Use this switch to select other CHs when the
CH16 switch is set to the CH position. The
speaker makes alarm buzz when no
preprogrammed channel is selected.
(17) SQ(squelch) control
Turning it fully counterclockwise opens the
squelch. As it is turned clockwise, higher input
level is reguired to open the squelch.
3.2 Operating Procedure
3.2.1 Preparation
(1) Set a desired channel number.
(2) Turn the squelch control fully
counterclockwise.
(3) Turn the PWR/VOL control clockwise.
Just after the power is turned on, noise is
heard from the speaker. Adjust sound
volume properly by turning the PWR/VOL
control.
(4) Turn the SQ control until noise from the
speaker is suppressed. Turn the SQ control
a little clockwise from that position. Do not
turn it too much, because the squelch will
not open when a weak signal is received.
Thus, radiotelephone is in stand –by mode,
and ready for reception.
3.2.2 Call
(1) While holding down the PTT button on the
left side of the radiotelephone, call up the
partner station (called Station A for now).
(Depressing the PTT button lights up the
Tx lamp.)
Calling is performed as described below.
Example:
“Station A, Station A, this Station B.
How do you read please.”
Release the PTT button to set the
equipment ready for reception as soon
as this call is over, and wait for an
answer from Station A.
Station A may reply in such a manner
as shown below;
“Station B, Station B, this is Station A,
I’ve gotten you, please.”
Since this radiotelephone employs the
press-to-talk communication system,
only one-way message is available.
Therefore, with the aim of smooth
conversation, it is preferable to insert a
word “please” or “over” at the end of
each speech as shown in the above
examples before releasing the PTT
button.

5
(2) As soon as you get an answer from the
partner station, inform it of the receiving
conditions using numbers shown in Table
3-1 below.
Example:“The sensitivity and clarity of
your talk is 4. How much is
our sensitivity and clarity?
Please.”
Table 3-1
Sensitivity
/clarity
Receiving
condition
1 Extremely
poor
2 Poor
3 Normal
4 Good
5 Excellent
3.2.3 Closing down
Turn the PWR/VOL control fully
counterclockwise to turn off the power. If you
leave the power on, the secondary battery will
have excessive discharge and deteriorated
greatly.
3.3 Replacement of Battery Pack NBB-248/248A /389
(1) Removal
While holding down the PUSH button on the
left side of the radiotelephone, twist Battery
Pack counterclockwise. (See Figure 3-3.)
(2) Mounting
Align the concave on the top of the battery pack
with the convex on the bottom of
radiotelephone. Twist the battery pack
clockwise until you feel a click, it is not
necessary to press the PUSH button.
Figure 3-3

6
3.4 Handling of Battery Charger
NBA-4141/NBA-4141A (Optional)
3.4.1 Installation
The battery charger can be installed on a desk
top or on a wall. Figures 3-4, 3-5, and 3-6
illustrate how to install it.
When it is installed on a wall, the fixing angle A
may be 0°, 30°, or 45°. If its location needs to
be changed from a desk top to a wall, change the
position of the fittings as shown in Figure 3-7.
Figure 3-4 Example of
a Desk top mounting
Figure 3-5 Example of a bulk head
mounting : Example 1 (Fixing angel 0°)
Figure 3-6 Example of a bulk head
mounting : Example 2 (Fixing angel 30°)
Figure 3-7 Changing the Position of Fittings

7
3.4.2 Replacement of Fuse
(1) Remove the plug of the AC power cable for
the battery charger from the convenience
outlet.
(2) Remove the power supply terminal
protecting cover on the front of the battery
charger as shown in Figure 3-8.
(3) Remove the fuse from the fuse holder, and
mount a new fuse. Use a 250V, 0.5A, 5.2×
20L fuse.
(4) Put back the cover.
3.4.3 Change of Power Supply Voltage
AC105, 115, 210, or 230 V can be selected by
changing among the taps on the internal
transformer. A soldering iron is needed for the
change.
(1) Remove the plug for the AC power supply
cable for the battery charger.
(2) Remove the power supply terminal
protecting cover as shown in Figure 3-8,
(3) Remove five screws from the bottom of
Battery Charger. (See Figure 3-9.)
(4) Remove the outer cover. (See Figure 3-8.)
(5) Solder the cable to any desired voltage
terminal of the power transformer. (See
Figure 3-10 and Table 3-2 .)
(6) Assemble the battery charger properly.
3.4.4 Parallel Wiring of Power Cables
It is advisable to put the power cables in parallel
when several battery chargers are used.
In the following example, three battery chargers
are used. No wiring materials are necessary
because the attached cables are used after
cutting it.
(1) Determine the locations of battery
chargers and the suitable length of cables
for wiring.
(2) Remove the power supply terminal
protecting covers. (See Figure 3-8.)
(3) It is not necessary to remove the attached
power cables from the terminal boards.
(4) According to the wiring diagram shown in
Figure 3-11, cut and connect the attached
power cables for the first two battery
chargers. For easy work, the attached
crimp-style terminals may be used. It is
not necessary to cut the power cable of the
remaining battery charger.
(5) Put back the power terminal protecting
cover.
(6) Insert the plug of the power cable of the
last battery charger into the AC
convenience outlet.
Power Supply Voltage Terminal of the
power transformer.
AC100V ～ 110V 105 V
AC115V ～ 120V 115 V
AC200V ～ 220V 210 V
AC230V ～ 240V 230 V
Figure 3-8
Figure 3-9 Figure 3-10
Figure 3-11
Table3-2 Power Supply Voltage vs
Terminal of the power transformer.

8
3.5 Handling of the Accessories
3.5.1 Carrying Strap
The attached carrying strap facilitates carrying
the radiotelephone on shoulder. To fasten the
strap, use the two fittings on the upper part of
the radiotelephone as shown in Figures 3-12 and
3-13. Additionally, do not unlink the weak links of
the strap in the unnecessary situation to avoid
the malfunction.
And always check whether the weak links are
covered with rust or not. If any rust is found on
the weak links, replace the strap with the new
one.
3.5.2 Belt Clip
The belt clip allows the radiotelephone to be
attached to one’s belt or breast pocket. Press the
top of the belt clip to open its lower part as shown
in Figure 3-14, and hook it to your belt.
3.5.3 Connecting of the Earphone and External
Speaker/Microphone
Connect the optional earphone 6UMJD00004 and
external speaker-microphone 6UMJD00029
to the RMT (remote terminal) connector on the
radiotelephone as shown in Figure 3-15.
Either the earphone or the speaker/microphone
can be connected and used.
3.5.4 Lithium Primary Battery
NBB-389 is the primary battery for the
emergency use only. Do not charge this battery.
Since this battery is equipped with a non-
replaceable seal to indicate that it has not been
used, do not detach the seal excluding the
emergency.
Check the expiry date regularly and be careful
not to become invalid.
The shelf life of this battery is five years.
Figure 3-14
Figure 3-12
Radiotelephone with
Carrying Strap Fastened
Figure 3-13
Fastening of
the Carrying Strap
Figure 3-15

9
4. BATTERY CHARGING
NOTE: DO NOT charge the NBB-389 primary battery.
4.1 Period of time to charge
When the battery energy is almost consumed, the
BUSY lamp blinks to indicate it. Charge the
battery whenever the BUSY lamp begins to blink.
4.2 Precautions on Charging
(1) Charging should never be done at a
temperature below the freezing point.
(2) For charging, always use the attached battery
charger NBA-4141/NBA-4141A.
(3) Even when the radiotelephone is not used for
a long period, it is requested to charge the
battery every three months.
(4) IF the battery charger is not fixed on a desk or
bulkhead, put in a stable position.
(5) Never touch the charging terminals with a
metallic bar or bare hand. When the plug is
inserted to the AC convenience outlet, an
output immediately appears at the charging
terminals.
(6) Do not perform transmission during charging.
(7) Detach the carrying case from the
radiotelephone.
4.3 Charging Procedure
(1) Attach the AC plug of the battery charger
NBA-4141/NBA-4141A to the convenience
outlet.
(2) Turn off the JHS-7, and insert the battery
pack into the battery charger, as shown in
Figure 4-1, with or without the radiotelephone
mounted on the pack. It is not possible to
insert the pack in a direction different from
that shown in the figure because of a
preventing mechanism.
When the battery pack is inserted correctly,
the QUICK lamp lights up red, and quick
charging begins.
(3) When quick charging is complete, the QUICK
lamp goes out. Then, the TRICKLE lamp
lights green, indicating that trickle charging
begins.
With the charger in this condition, the battery
pack is fully charged, and charging is
complete. Since trickle charge makes up for
the natural discharging of the battery pack,
the battery back is always charged fully as
long as in the trickle charge condition after
quick charge.
(4) Both the "QUICK" and "TRICKLE" LEDs start
flashing, if there is abnormal to the battery. In this
case, remove battery and do not insert it until the
LEDs stop flashing.
Figure 4-1 Inserting of Battery Pack

10
5. MAINTENANCE AND INSPECTION
5.1 Daily Maintenance
The life of an equipment like the radiotelephone
largely depends on the quality of maintenance. It is
very important to check the radiotelephone
regularly to keep it in its best condition. Regular
inspection helps to find a symptom of trouble or
prevent trouble before it occurs. It is quite desirable
to perform routine inspection and maintenance
every day according to Table 5-1 below.
Table 5-1 Routine Checking
Step Checking
item Description
1 Battery The BUSY lamp on the panel
should not be blinking. If it
blinks, charge the battery.
2 PWR/VOL
control
A
s you turn the control, the
power should be turned on,
and sound volume should be
increased gradually.
3 SQ control Noise should be eliminated
quickly when the SQ control
is turned clockwise.
4 Transmit
output
The Tx lamp should be
turned on during
transmission.
5 Transmitting
and receiving
condition
Normal communication
should be performed with
partner stations.
5.2 Regular Inspection
Conduct talking test once a month at least to check
functions of the radio telephone. Check the expiry
date regularly and be careful not to become invalid.

11
6. TROUBLESHOOTING
6.1 Precautions
(1) Exclusive wrench is needed to remove the
antenna from the radiotelephone. If the
removal is forced by any other means, the
antenna or the radiotelephone will be
damaged. Ask a nearest JRC dealer or branch
if the removal is necessary.
(2) Before making repairs or asking for repairs,
check fundamental matters such as operating
procedures and battery conditions.
(3) Unless having suitable measuring
instruments or qualification to make repair,
never disassemble this equipment.
(4) When disassembling this equipment, refer to
Figure 6-1.
6.2 Troubleshooting Guide
NO Trouble Possible
cause
Counter-
measure
1 CH indicator
does not light
during power
on.
(1)Battery
discharged
(2)PS circuit
failure
(1)Charge
battery
(2)Check
voltages
2 No sound
comes out
although
BUSY lamp
is on.
(1)Speaker
wire break
(2)Loose
contact in
connector
(3)AF amp
failure
(1)Replace
speaker
(2)
Check
connector
and speaker
cable
(3)Check the
AF amp
3 BUSY lamp
off and no
voice heard.
(1)Squelch
closed
(2)IF amp
failure
(1)Turn SQ
control
fully
counter-
clockwise
(2)Check IF
amplifier
4 CH16 lamp
blinks but
no voice
heard.
Synthesizer
failure
Check
synthesizer
5 Tx lamp does
not light
during
transmitting.
Transmitter
failure
Check
transmitter
6 Despite Tx
lamp lighting,
communication
unavailable.
Using a
different
channel.
Make sure of
channel No.
Figure 6-1 Assembly Drawing of the Radiotelephone

12
6.3 Simple Adjustment
This subparagraph describes simple adjustment
procedure that can be followed without use of
special measuring instruments.
Before simple adjustment, perform the following
initial settings:
(1) SQ control Turned fully counter
clockwise
(2) Channel number: CH16
(3) PWR/VOL switch: Upon adjustment,
turned clockwise to
switch on the power.
6.3.1 Checking of Voltages
The power supply voltage should be 7.2V.
step signal Check
point
Measuring
equipment
Measurement
(standard)
1 7.2V J201
pin 8
Circuit tester
or digital
voltmeter
7.2V
2 5V J202
pin 8
Circuit tester
or digital
voltmeter
5V
3 R5 J201
pin 1
Circuit tester
or digital
voltmeter
5V during Rx
0V during Tx
4 S5 J202
pin 10
Circuit tester
or digital
voltmeter
5V
5 T7 J202
pin 1
Circuit tester
or digital
voltmeter
0V during Rx
7V during Tx
6.3.2 Adjustment of the Synthesizer
Connect a digital voltmeter to the check point ③
on the CMN-241 main unit.
step control Check point Procedure
1 CV2 CMN-241
③
Set the voltage at
2.5V DC ±0.1V
for reception.
2 CV3 CMN-241
③
Set the voltage at
2.5V DC ±0.1V
for transmission.
6.3.3 Frequency Adjustment
(1) Connect a simple whip antenna to the
input terminal of the frequency counter.
(2) Bring the antenna of the radiotelephone
near the antenna of the frequency counter,
and put the radiotelephone in
transmission mode.
(3) Adjust CV3 on the CMN-241 main unit so
that the frequency may be set at 156.8MHz
±100Hz
6.3.4 Transmit Output Adjustment
(1) Remove the antenna using the exclusive
wrench.
(2) Connect a power meter (50Ω) to the
antenna terminal.
(3) Adjust RV1 on the CMN-241 main unit so
that the transmit output may be 0.8W±
20%
6.3.5 Tuning of the Receiver
(1) Connect a standard signal generator (50Ω)
to the antenna terminal.
(2) Set the frequency and output level of the
standard signal generator at 156.8MHz
and 0dBμ, respectively.
(3) Adjust L5 through L8, T1, and T2 on the
CMN-241 main unit so that the noise from
the speaker may be minimized.

13
7. OPTIONS
The following options are available to make the best
use of the JHS-7.
7.1 Battery Charger NBA-4141/NBA-4141A
The battery charger is used to charge the battery
pack. The charging is possible with or without the
radiotelephone mounted on the pack. The battery
charger can be fixed to a desk top or a wall.
Attachments: Fuse(0.5a, 5.2×20L) ×
1, crimp style terminal
(R1 25-3) ×3, wood
screw×4
Power supply voltage: 100/120/220/240V AC
selected using a tap
(standard: 100V AC)
Input Frequency: 50Hz～60Hz
Applicable battery pack: NBB-248/248A
Charging time: Not more than 3 hours
Charging current: Quick 530mA15%
10%
Trickle 25mA±20%
Overall dimensions: 210(W)×100(H)×105(D)
Weight: Approx. 1.5kg
Operating Temperature: -10 ～ +50℃
7.2 Primary Battery Pack NBB-389
Battery Lithium-Manganese
Dioxide Battery
Capacity 9.0V, 4800mAH
Dimensions: 62(W) ×65(H) ×55(D)
Weight: Approx. 220g
7.3 Battery Pack NBB-248
Battery: Ni-Cd battery
Capacity 7.2V, 1000mAH
Dimensions: 62(W) ×54(H) ×41(D)
Weight: Approx. 200g
7.4 Battery Pack NBB-248A
Battery: Ni-MH battery
Capacity 7.2V, 1000mAH
Dimensions: 62(W) ×54(H) ×41(D)
Weight: Approx. 200g
7.5 Earphone 6UMJD00004
The earphone is helpful when voices from the
speaker are not clear due to noisy surroundings.
Impedance: 8Ω
Cable length: 1m
Weight: Approx. 20g
7.6 External Speaker/Microphone 6UMJD00029
The external speaker/microphone is helpful when
the radiotelephone is carried around one’s waist.
Microphone sensitivity: -66dB±4dB at
1kHz(0dB=1V/μbar)
Speaker output: 0.5W(8Ω)
Cable Curled cord
Overall dimensions: 64(W)×94(H)×35(D)
Weight: Approx. 280g
7.7 Carrying Case MPXP02368
The carrying case protects the surface of the
radiotelephone against damage.