Kenwood TM-621A User manual

GOO/ANA
144/220MHz FM DUAL BANDER
M-621A
144/440MHz FM DUAL BANDER
IM-721A
144/430MHz FM DUAL BANDER
IM-721A
TM-721E
INSTRUCTION MANUAL
KENWOOD CORPORATION
@©PRINTED IN JAPAN B50-8225-10(K, M, T.W)(T)
89/121110987654321 881211098

Thank you for purchasing this new transceiver.
IMPORTANT:
Please read this instruction manual carefully before placing
your transceiver in service.
SAVE THIS INSTRUCTION MANUAL.
CAUTION: —— -
Long transmission or extended operation in the HI power
mode might cause the rear of this transceiver to get warm.
Do not place the transceiver where the heat sink (rear panel)
might come in contact with plastic or vinyl surfaces.
This Instruction Manual covers the following models.
TM-621A : 144/220 MHz FM DUAL BANDER
TM-721A : 144/440 MHz FM DUAL BANDER
(U.S.A. version)
TM-721A : 144/430 MHz FM DUAL BANDER
(Other market)
TM-721E : 144/430 MHz FM DUAL BANDER
(with Tone Burst for U.K. version)
The following explicit definitions apply in this manual:
Note : If disregarded, inconvenience only, no risk of
equipment damage or personal injury.
Caution : Equipment damage may occur, but not per-
sonal injury.
Illustrations show the TM-721A.

CONTENTS
Pioh>
BEFORE OPERATION 4
SPECIFICATIONS and ACCESSORIES . a6
INSTALLATION INSTRUCTIONS ... as
OPERATION ie vin csnntgs nnn esispicensnspiivsadveredeavenses 10
OPERATING CONTROLS
RECEIVER OPERATION. s.vesencoscossneivses esses een 15
Reception
Frequency Selection
Frequency Step Selection ie
A.B.C. (Automatic Band Change) .............0+ 18
Beep Tone
TRANSMITTER OPERATION
REPEATER OPERATION ...0.ce3tvasivauasitecseaseeas
Transmitter Offsets
Reverse Function
Tone Operation
Autopatch (U.S.A. version only)
MEMORY 7.05 s25e sins shswcasennasacsdcteuansecuvee este
Microprocessor Memory Back-up
Microprocessor Initialization
Memory Channel
Memory Contents
Memory Enithyiscistesesescectssssevecssnexsas ceases 23)
Simplex/Normal SHIFT
Odd Split Channel
Call. CHANG) aides nnsnexrcinesnasnsinediiencwexe 25
Memory Recall
Memory Shift
Scan Options
Programmable Band Scan/Band Scan
Memory Channel Scan
Hold Resume Programming
Priority Alert, ccscssousesveceurascsarsacetiaewsserews 27
Memory Channel Lockout
BLOCK DIAGRAM
and
SCHEMATIC
DIAGRAM
°7"""""
another
sheet
MAINTENANCE.....
in Case of Difficulty ....
OPTIONAL ACCESSORIES....
CTCSS unit TSU-6 (U.S.A. version) ...
REMOTE CONTROLLER RC-10....
REFERENCE

1.
BEFORE
OPERATION
Safety
precautions
The
power
requirement
is
13.8
VDC.
Never
remove
the
case
unless
instructed
to
do
so
in
this
In-
Never
attempt
connection
to
a
24
VDC
source.
struction
Manual.
If
the
internal
parts
are
touched
acciden-
BBUny
of
2
tally, a serious electric shock might occur.
DC Power Supply:
Touching
the
power
plug
when
your
hands
are
wet
may
result
in
a
serious
electric
shock.
Never touch internal parts.
F
vie
F
~Qury
If
a
metal
object,
such
as
a
hair
pin
or
a
needle,
comes
into
4
\
contact
with
the
power
socket
on
the
rear
panel,
a
o*
%\___
Never
touch
with
wet
hands.
dangerous
electric
shock
may
result.
Never
permit
children
jp
to
put
anything,
especially
metal
objects,
inside
this
unit.
DC Power Supply:
Never pull, bend or extend the power cord. This could
damage the power cord, resulting in a broken cord or short-
circuit.
Always grasp the plug.

Installation notes
Do not place this unit in a location that is exposed to direct
- sunlight, near a heating appliance, etc.
Oe
.
pV
Do not store or use the unit in a dusty location or in a moist
atmosphere. Select a location where there is good ventila-
tion.
In case of an abnormal odor
If an abnormal odor or smoke is detected, immediately turn
the power OFF and pull out the power cord. Contact your
dealer or nearest Service Station.
(3
To maintain good ventilation, do not put books or papers on
the unit. Position the unit at least 10 cm away from the
walls.
Cleaning
Do not use volatile solvents such as alcohol, paint thinner,
gasoline, benzine, etc. to clean the cabinet. Use a silicone
cloth or a clean dry cloth.
Silicone cloth Thinner Benzine

2. SPECIFICATIONS AND ACCESSORIES
2-1. SPECIFICATIONS
TM-721A
‘eure Other markets TM-721E TM-621A
version
Frequency range
144 to 148 MHz|144 to 148 MHz|144 to 146 MHz|144 to 148 MHz.
438 to 450 MHz/|430 to 440 MHz|430 to 440 MHz/220 to 225 MH:
Mode
F3E (FM)
Antenna impedance
50 ohms
Power requirements
13.8 VDC +15%
Ground
Negative _
Less than 9.5 A
5G] Receive mode with no
135] signal
rf Transmit mode
Less than 0.6 A
Operating temperature
— 20°C to +60°C (—4°F to +140°F)
Dimensions (W x H x D)
(Projections included)
150 x 50 x 219 mm (5.9 x2" x 8.6")
Weight
1.8 kg (3.97 Ibs)
Output
power*
144 MHz: 45 W, 220 MHz: 25 W, 430/440 MHz: 35 W
5W
Modulation
Reactance modulation
| Spurious radiation
Less than -60 dB
Maximum frequency deviation
+5 kHz
Audio distortion (at 60%
modulation)
Less than 3% (300 to 3000 Hz)
Microphone impedance
500 to 600 ohms
Circuitry
Double conversion superheterodyne
U.S.A, version
Intermediate
144 MHz: 16.9 MHz/455 kHz,
220 MHz: 30.825 MHz/455 kHz,
440 MHz: 21.6 MHz/455 kHz
frequency
Other market
144 MHz: 10.7 MHz/455 kHz,
430 MHz: 30.825MHz/455 kHz
2)| Sensitivity(12 dB SINAD)
144 MHz: Less than 0.2 uV, 220 MHz: Less than 0.18 2V,
430/440 MHz: Less than 0.16 wV
Selectivity
—6 dB: More than 12 kHz,
— 60 dB: Less than 24 kHz
Spurious response
Better than 60 dB
Squelch sensitivity
Less than 0.09 «V
Output
More than 2 W across 8 ohms load (5% distortion)
External
Notes:
8 ohms
1. Circuit and ratings are subject to change without notice due to ad-
vancement in technology.
2. *: Recommended duty cycle:
1 minute : Transmission, 3 minutes : Reception
2-2. ACCESSORIES
Unpack your new transceiver carefully, and con-
firm that the accessories listed below are included
in the box.
MC-48B DTMF Microphone
(U.S.A. only) .........0086 791-0359-15..... 1 ea.
or
Dynamic Microphone...... T91-0365-15..... 1 ea.
Microphone Hook
(U.S.A. (only): ......2.00008 J20-0319-24...... 1 ea.
Self tapping Screw
(U.S.A. only) .. -N46-3010-46 .
Mobile Mounting Kit
Bracket
SEMS Screw ..
Self tapping Screw.
-N99-0318-05.....1 ea.
-J29-0418-03...... 1 ea.
-NO9-1530-05.....4 ea.
-NO9-0335-05 .....4 ea.
Flat Washer.sc..,csossensnsaenivsovpaccaresysaonees
DC Power Cable -E30-2111-05 .
Fuse (10A) -FO5-1031-05.....
Instruction Manual ......... B50-8225-XX ..1 copy
Warranty) Cards: caamccsssssevecscgarsececcssnetone 1 ea.
After unpacking
Shipping container:
Save the boxes and packing in the event your unit
needs to be transported for remote operation, main-
tenance, or service.

3. INSTALLATION INSTRUCTIONS
3-1. INSTALLATION
Mounting Bracket
When installing the transceiver in a vehicle consider the
ease of operation and safety when selecting the location
for the mounting bracket.
1. Install the bracket using
the supplied flat washers Flat
and self tapping screws (4 __ washer —~
Self tapping —-
pcs. each). seid
2. Attach the transceiver
loosely using the SEMS
screws (4 pcs.).
3. The angle of the bracket
may be adjusted to any of
9 possible viewing angles.
Select the desired angle. Fig. 1
(Fig. 2)
4. Hold the transceiver in
place and tighten the 4
SEMS screws using a
wrench or screwdriver.
3-2. CONNECTIONS
3-2-1. Mobile Installations
TM-721A/721E:
The MA-4000 dual band
antenna is recommended.
To 144 MHz antenna
The SP-40 or
= the SP-50B is
_ recommended. _
¥ External a)
Duplexer \
- Pp
+
TM-621A: TM-721A/721E:
To
144
MHz
To
430
MHz
To
220
MHz
To
430/440
MHz
antenna = antenna
Cautions:
1. Before installing the power cable, be sure to remove the
negative lead from the battery for safety.
2. After installation and wiring, be sure to double check for
correct installation before reconnecting the negative
lead to the battery terminal.
3. If the fuse opens, be sure to check that each conductor
has not been damaged by short-circuiting, etc.
Then replace with a new fuse of the same rating.
4. After completing the wiring, wrap the fuse holder with
heat resistant tape to protect against heat and moisture.
5. Do not remove the fuse even if the power cable is too
long.

A. Battery Connections
Connect the power cable directly to the battery terminals.
Use of the cigarette lighter socket can lead to poor connec-
tion, and result in poor performance. Pay close attention to
the polarity of the cables when connecting them to the bat-
tery.
Make sure the positive (+) and negative (—) lead polarity is correct
when connecting to the battery.
Red
Engine compartment -—}|—-~ Passenger compartment
Fuse
To the
transceiver
Select a location where
E power cable is pro- brargpondet bran pmo
does not directly con
tact the edge of the hole
¢ by using a grommet.
Chassis or
fire wall
tected from heat, mois-
ture or abrasion when
securing
Battery
the cable.
@ lf the wiring hole in the fire wall or chassis is too small,
disassemble the fuse holder to thread the wire through the hole.
From passenger
compartment
oy ——————
Thread like this
B. Ignition Noise
This transceiver has been designed to suppress ignition
noise; however, if excessive noise is present, it may be
necessary to use suppressor spark plugs (with resistors).
3-2-2. Fixed Station
A regulated DC power supply (13.8 VDC capable of sup-
plying at least 10 Amperes) is required. The PS-430 and
the PS-50 are recommended.
CAUTION:
. Never connect the AC power cable to the AC outlet until
1
2.
all other connections have been made.
Before connecting and disconnecting the power connec-
tor, be sure to turn off the POWER switches of both the
transceiver and the DC power supply.
. Observe polarity of the DC power cable. The transceiver
operates on 13.8 VDC, negative ground. Battery polari-
ty must be correct. The power cable is color coded:
Red — + (Positive polarity)
Black — — (Negative polarity)
f
+
To
144
MHz
antenna
+
[ ? TM-621A or SP-430
6
—
TM-621A : To 220 MHz antenna
TM-721A/721E : To 430/440 MHz antenna

3-2-3. Antenna
The type of antenna that is used will greatly affect the per-
formance of the transceiver. Use a properly adjusted anten-
na, of good quality, to enable your transceiver to perform at
its best. The antenna input impedance is 50 ohms. Use
50-ohm coaxial cable such as RG-8U or 8D-2V for this
connection. If the antenna is far from the transceiver the
use of low loss coaxial cable, such as RG-8U is recom-
mended. Match the impedance of the coaxial cable and
that of the antenna so that the SWR is less than 1.5 to 1.
The protection circuit in the transceiver will activate if the
SWR is particularly poor (greater than 3 to 1).
High SWR values will cause the transmitter output to drop,
and may lead to TVI or BCI reports.
Caution:
For protection against fire, electric shock, personal injury,
or damage to the radio, use a lightning arrester in your
antenna lines.

4. OPERATION
4-1. OPERATING CONTROLS
4-1-1. Front Panel ® ®@ 3@ a 46 a 6
+ +) || mom scan = 7 goliney | ereas
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® wo i @ (09
(@) Main Tuning control ® VFO key
This
control
is
used
to
select
the
desired
transmit/
This
key
is
used
to
return
to
VFO
operation
after
oper-
receive frequency, Memory Channel, Frequency Step, ating in the MR (Memory Recall), or CALL Channel mode
Tone Frequency, and Scan direction of the MAIN fre- (TM-621A/721A only).
quency band. The MAIN tuning control will increase frequency in the
@ CALL key (TM-621A/721A) selected step size, the tone frequency (TM-621A/721A
The CALL key selects the CALL channel of the MAIN only), and/or the frequency step.
frequency band. The frequency has been factory-set as @ MR/M key
follows, but may be reset to any desired frequency. (See This key is used to select Memory Recall operation af-
CALL Channel P25.) ter operating in the VFO or CALL channel mode. The
TM-621A ; 220.000/144.000 MAIN Tuning control may be used to select the desired
TM-721A memory channel in this mode.
U.S.A. version ; 440.000/144.000 ® VOL control/Power switch
Other market + 430.000/144.000 The volume control and power switch are combined.
TONE key (TM-721E) Rotating the control clockwise will turn ON the tran-
European version: This key is used to transmit a Tone sceiver.
signal. When the key is depressed the repeater con- Advancing the control further clockwise will increase
trol signal of 1750 Hz is activated. the total volume of two bands. The BALANCE control
U.K. version: This key is used to activate the proportions the volume among the two bands.
1750 Hz tone burst. © MAIN SOL control
This control is used to select the desired SOL threshold
level of the MAIN frequency band.
10