Kenwood Tk-290 User manual

Document Copyrights

No part of this manual may be reproduced, translated, distributed, or transmitted in any

form or by any means, electronic, mechanical, photocopying, recording, or otherwise, for

any purpose without the prior written permission of Kenwood.

Disclaimer

While every precaution has been taken in the preparation of this manual, Kenwood

assumes no responsibility for errors or omissions. Neither is any liability assumed for

damages resulting from the use of the information contained herein. Kenwood reserves

the right to make changes to any products herein at any time for improvement purposes.

B51-8423-10 (N)1023

VHF FM TRANSCEIVER

TK-290

SERVICE MANUAL

Photo is TK-290 K type.

Does not come with antenna.

Antenna is available as an option.

CONTENTS

GENERAL ................................................................. 2

SYSTEM SET-UP ..................................................... 2

OPERATING FEATURES ......................................... 3

REALIGNMENT...................................................... 11

CIRCUIT DESCRIPTION......................................... 17

SEMICONDUCTOR DATA..................................... 25

DESCRIPTION OF COMPONENTS ....................... 26

PARTS LIST ............................................................ 28

EXPLODED VIEW .................................................. 36

PACKING ................................................................ 37

DISASSEMBLY FOR REPAIR ................................ 38

ADJUSTMENT ....................................................... 39

PC BOARD VIEWS

FINAL UNIT (X45-3592-71) ............................... 50

CONTROL UNIT (X53-3930-XX)....................... 51

TX-RX UNIT (X57-5390-10) .............................. 55

SCHEMATIC DIAGRAM ........................................ 61

BLOCK DIAGRAM.................................................. 67

LEVEL DIAGRAM ................................................... 69

TERMINAL FUNCTION .......................................... 70

KNB-17A (Ni-Cd BATTERY) ................................... 71

KMC-25/26 (SPEAKER MICROPHONE) ................ 72

KSC-19 (CHARGER) ................................................ 73

KSC-20 (RAPID CHARGER) .................................... 73

KPG-36 (PROGRAMMING INTERFACE CABLE)

...... 73

KRA-14 (HELICAL ANTENNA) ............................... 73

SPECIFICATIONS............................... BACK COVER

CAUTION

When using an external power connector,

please use with maximum final module protec-

tion of 10V

REVISED

Antenna

(KRA-14 : Option)

Cabinet assy

(A02-2139-63)

Knob assy (SEL)

(K29-5282-04)

Knob assy (VOL)

(K29-5283-04)

Panel assy

(A62-0537-53)

Knob assy

(Side key)

(K29-5441-04)

TK-290 GENERAL / SYSTEM SET-UP

INTRODUCTION

SCOPE OF THIS MANUAL

This manual is intended for use by experienced techni-

cians familiar with similar types of commercial grade com-

munications equipment. It contains all required service in-

formation for the equipment and is current as of the publica-

tion data. Changes which may occur after publication are

covered by either Service Bulletins or Manual Revisions.

These are issued as required.

ORDERING REPLACEMENT PARTS

When ordering replacement parts or equipment informa-

tion, the full part identification number should be included.

This applies to all parts : components, kits, or chassis. If the

part number is not known, include the chassis or kit number

of which it is a part, and a sufficient description of the re-

quired component for proper identification.

PERSONNEL SAFETY

The following precautions are recommended for person-

nel safety :

• DO NOT transmit until all RF connectors are verified se-

cure and any open connectors are properly terminated.

• SHUT OFF and DO NOT operate this equipment near

electrical blasting caps or in an explosive atmosphere.

• This equipment should be serviced by a qualified techni-

cian only.

SERVICE

This radio is designed for easy servicing. Refer to the

schematic diagrams, printed circuit board views, and align-

ment procedures contained within.

NOTE

WE CANNOT guarantee oscillator stability when using

channel element manufactured by other than KENWOOD or

its authorized agents.

FCC COMPLIANCE AND TYPE NUMBERS

Model

Type acceptance number

Frequency range

Compliance

TK-290 ALH21893110 136~174MHz Parts 22,74,80,90

Unit X57-539X-XX X53-393X-XX X45-359X-XX DTMF

Model & Frequency range Remarks keypad

destination 0-10 0-11 0-12 2-71

TK-290 K ✓✓ ✓136~174MHz 1st IF : 44.85MHz –

K2 ✓✓✓136~174MHz LOC : 45.305MHz ✓

Merchandise received

License and frequency allocated by FCC

Choose the type of transceiver

Transceiver programming

Are you using the optional antenna?

Delivery

Are you using the speaker microphone?

TX/RX 136~174 5W TK-290 K,K2

Frequency range (MHz) RF power Type

A personal computer (IBM PC or compatible), programming

interface (KPG-36), and programming software (KPG-38D)

are required for programming.

(The frequency, and signalling data are programmed for the

transceiver.)

YES

YES YES

NO NO

KRA-14

Helical antenna

(Option)

With

antenna?

KMC-25

KMC-26

SYSTEM SET-UP

TK-290

OPERATING FEATURES

1. Getting Acquainted

1-1. Key Descriptions

TX/Busy/Battery low indicator

Lights red while transmitting. Lights green while receiv-

ing. Flashes red when the battery power is low while

transmitting; replace or recharge the battery.

Note : This indicator can be disabled by your dealer.

Power switch/Volume control

Turn clockwise to switch ON the transceiver. Turn coun-

terclockwise, until a click sounds, to switch OFF the

transceiver. Rotate to adjust the volume level.

Selector

Rotate this control to activate its programmable function

(Page 8).

Toggle switch

Switch the toggle position to activate its programmable

function (Page 8).

Top 1

Top 2

Orange

Side 1

Side 2

PTT (Push-To-Talk) switch

Press this switch, then speak into the microphone to call

a station.

Press these PF (programmable function)

keys to activate their programmable func-

tions (Page 8)

DTMF keypad (keypad models only)

Press the keys on the telephone keypad to send DTMF

tones.

Universal connector

Connect the external speaker/microphone (optional)

here. Otherwise, keep the supplied cover in place.

1-2. Display

Alphanumeric display

Displays the operating group or channel number, or the

group or channel name. When making a DTMF or 2 Tone

call, the display will alternate between CALL and the

channel. Also displays various menu functions.

7 Segment display

Displays the operating group or channel number. Also

displays tA (Talk Around), P1 (Priority1), P2 (Priority2), PP

(Priority1 and Priority2), or HC (Home Channel); depend-

ing on the function being used.

A (Add) indicator

Appears when a channel is added to the scanning se-

quence.

SCN (Scan) indicator

Appears when Scan mode is active.

MON (Monitor) indicator

Appears when the monitor function is active.

LO (Low) indicator

Appears when low power is selected.

OPT indicator

Appears when Operator Selectable Tone is enabled.

AUX (Auxiliary) indicator

Appears when Aux is ON. Appears and blinks when the

optional scrambler board is enabled.

Note : The alphanumeric and 7 segment displays can be

inverted if a PF key or the toggle switch is programmed

with Invert Display (Page 8).

ABAB

SMA male type

antenna connector Battery pack

release latch

Microphone

Display

Speaker

TK-290

2. Scan Operating

2-1. Scan Types

•Single Group Scan

You can scan all valid (ADD) channels in the displayed

group that can be selected with the group selector.

•Multiple Group Scan

You can scan all valid (ADD) channels in the all valid

(ADD) group.

2-2. Scan Start Condition

One or more non-priority channels must be added to all

channels that can be scanned. The transceiver must be in

normal receive mode (PTT off).

When you activate the key or the toggle switch (to right

position) programmed to the scan function, the scan starts.

The scan icon “SCN” lights and “SCAN” or revert channel

(programmable) is indicated on 7-digit alphanumeric display.

2-3. Scan Stop Condition

The scan stops temporarily if the following conditions are

satisfied.

1) A carrier is detected, then signalling matches on chan-

nels for which receive the signalling is set by the pro-

gramming software.

2) A carrier is detected on the channel for which receiving

signalling is not set by the programming software or

when the monitor (signalling cancel) function is activated.

2-4. Scan Channel Types

1) Priority channel 1 is the most important channel for the

scan, and always detects a signal during scan and when

the scan stops temporarily.

2) Priority channel 2 is the next important channel for the

scan, and always detects a signal during scan and when

the scan stops temporarily at a channel other than priority

channel 1.

3) Non-priority channels detects a signal during scan. For

the channels that can be selected with the group or chan-

nel selector when the scan does not occur, adds an indi-

cator “A” lights.

2-5. Priority Channel Setting

Priority channels 1 or 2 can be set as follows with the

programming software (KPG-38D).

1) Specify priority channels 1 or 2 as fixed priority channels.

2) Make selected channels, priority channels.

3) Operator delectable

Specify the initial channel before the operator changes it.

2-6. Scan Type According to the Priority Channel

1) When no priority channels are set : Only the non-priority

channels are scanned.

If a non-priority channel stops temporarily, it stops until

there is no signal on the channel.

OPERATING FEATURES

2) When one priority channel is set : Either priority channel

1 or 2 is scanned.

If a non-priority channel stops temporarily, a priority chan-

nel signal is detected at certain intervals.

If a priority channel stops temporarily, it stops until there

is no signal on the priority channel.

3) When two priority channels are set : The non-priority

channel, priority channels 1 and 2 are scanned.

If a non-priority channel stops temporarily, priority chan-

nel 1 and 2 signals are detected at certain intervals.

If priority channel 2 stops temporarily, the priority chan-

nel 1 signal is detected at certain intervals.

If priority channel 1 stops temporarily, it stops until there

is no signal on priority channel 1.

2-7. Revert Channel

The revert channel is used to transmit during scanning

and set by the programming software (KPG-38D).

1) Priority 1

The transceiver reverts to the priority channel 1.

2) Priority 1 with talkback

The transceiver reverts to the priority channel 1.

If you press PTT during a resume timer (dropout delay

time, TX dwell time) or calling, you can transmit on cur-

rent channel to answer to the call however revert channel

is set to priority channel 1.

After resume time, scan re-starts and transmission chan-

nel is return to priority channel 1.

3) Priority 2

The transceiver reverts to the priority channel 2.

4) Priority 2 with talkback

The transceiver reverts to the priority channel 2.

If you press PTT during resume timer (dropout delay

time, TX dwell time) or calling, you can transmit on cur-

rent channel to answer to the call however revert channel

is set to priority channel 2.

After resume time, scan re-starts and transmission chan-

nel is return to priority channel 2.

5) Selected channel

The transceiver reverts to the channel before scanning or

the channel that you changed during scan.

6) Last called channel

The transceiver reverts to the last called channel during

the scan.

7) Last used channel

The transceiver reverts to the last used (transmitted)

channel during scan. “Last used” revert channel in-

cludes talkback function.

8) Selected with talkback

The transceiver reverts to the channel before scanning or

the channel that you changed during scan.

2-8. Scan End

When you reactivate the key or the toggle switch (to left

position) programmed to the scan function during scan

mode, the scan ends.

The scan icon “SCN” and “SCAN” or revert channel (pro-

grammable) display goes off.

TK-290

2-9. Temporarily Delete/Add

It is possible to delete or add channel temporarily during

scan. When scan stops on unnecessary channel for ex-

ample by interference of the other party, activate the delete/

add function (for example press the key), then that channel

is deleted temporarily and scan re-start immediately.

When you would like to add the deleted channel tempo-

rarily to scan sequence, select the desired (deleted) channel

during scan, activate the delete/add function (for example

press the key) before scan re-start.

That channel is added temporarily to scan sequence. The

temporary deleted or added channels are returns to pre-set

delete/add, when the transceiver exits from scan mode.

3. Optional Features

You can use these features using the programming soft-

ware (KPG-38D).

3-1. Alphanumeric Display (Group/Channel Name)

The programming software (KPG-38D) enables you to set

the alphanumeric display for group/channel name. The total

text size of group and channel name are 7-digits.

For example, If you set 2-digits for group name, then you

can use 5-digits for channel name. The characters can be

used as shown in Figure 1.

3-2. Beep Tones

The beep tones (power on tone, control tone, warning

tone, alert tone) are individually programmable to the fixed

level 0 to 31 or follow the mechanical volume position.

3-3. Minimum Volume

The minimum volume is programmable (0 to 31). The

transceiver remains the minimum volume level however the

mechanical volume position is set to zero.

ABCDE FGH I

JKLMNOPQR

STUVWXYZ

123456789

All on

Fig. 1

3-4. Squelch Threshold Level

Squelch threshold level value.

0 (Most loose)~15 (Most tight)

3-5. BCL (Busy Channel Lockout) Override

You can transmit in spite of Busy Channel Lockout situa-

tion. For example : To make an emergency voice call.

To transmit under busy channel lockout situation, press

PTT once more within approx. 500ms after the PTT release.

3-6. Selective Call Alert LED

You can select whether or not the LED on the transceiver

flashes in an orange color when Selective call was occurred.

3-7. Battery Warning

This transceiver has battery warning feature. If the low

voltage is detected during transmission, the transceiver

warns it by flashing red “LED”.

Then more low voltage is detected during transmission,

the transceiver stops transmission and warns it by flashing

red “LED” and beep.

Please notice “standard” for the battery exchange,

charging time by flashing red LED and beep.

3-8. Busy LED

You can program the enable or disable the busy “LED”

function when a carrier is detected. “Disable” saves battery

life.

3-9. TX LED

You can program the enable or disable the transmission

“LED” function.

3-10. 2-Digit 7-Segment Display

You can use 2-digit 7-segment the display to display the

channel number or group number. It is useful when the

main (7-digit 13-segment) display indicates group or channel

name.

3-11. Invert Display

Main (7-digit 13-segment) display and sub (2-digit 7-seg-

ment) display can be programmed to invert display.

It is easy to read the display when the operator sus-

pended the transceiver on a waste belt. The operator also

can change the display between normal and invert using

key. Refer the invert display function of key function.

3-12. Clear to Transpond

The transceiver waits the transpond of 2-Tone/DTMF if

channel is busy until channel open. This feature prevents

the interference to other party.

3-13. External Speaker

It can be selected if the receive sound is made by SP-Mic

SP or the main body SP at a SP-Mic mount.

3-14. Noise Cancelling MIC

Enable or disable the noise cancelling function of the in-

ternal microphone. It is not valid for the external SP/MIC.

OPERATING FEATURES

TK-290

3-15. Mode (Enable/Disable)

The transceiver has many special modes mainly for main-

tenance.

· Self Programming mode

· Panel Test mode

· Clone mode

· Firmware Programming mode

· Version info.

It is possible to set enable/disable for each mode. We

recommend to set these mode to Disable after set up to

save contents.

3-16. ID

The transceiver is capable to have ID. The format is

DTMF, MSK or ANI board (if installed). The timing that the

transceiver sends ID is programmable.

Connect ID : Connect ID is send on beginning of trans-

mission.

Disconnect ID : Disconnect ID is send on end of trans-

mission.

Both : Connect ID is send on beginning of transmission

and disconnect ID is send on end of transmission.

Off : Sending ID function is disabled.

There is also “PTT ID” setting for each channel. Refer

“PTT ID” of channel feature.

When you use an ID code for ANI board, the ID code and

transmitting timing are configured to the optional ANI board.

3-17. OST (Operator Selectable Tone)

The transceiver is capable to have “OST” function and

16 tone pair (QT/DQT) with max 7-digit name for each tone

pair.

•“OST”Back Up

The transceiver is programmable the selected “OST”

code is memorized or not. If you set to Disable (no memo-

rized), the “OST” function always starts at “off”.

•Direct “OST”

It is possible to call “OST” number directory using key-

pad. In this case, keypad is used for “OST”, then “DTMF

Auto PTT”, “DTMF Auto Dial” functions by keypad are not

usable.

3-18. Emergency

•Active Time

Automatic transmission period in the emergency mode.

•Interval Time

Interval time between the automatic transmissions.

•Duration of Locator Tone 1

Duration of an alert tone before the automatic transmis-

sion is performed.

•Duration of Locator Tone 2

Duration of an alert tone after the automatic transmission

is performed.

•Man Down Delay Time

Delay time of entering the emergency mode when the

internal Man Down port becomes active.

•Man Down Pre-alert

Wait time of the alert tone when the internal Man Down

port becomes active to enter the emergency mode. (After

an alarm sounds, the transceiver waits for the programmed

wait time then enter the emergency mode.)

•Emergency Channel Display

Setting for the display in the emergency mode.

The transceiver can be programmed to display “EMER-

GENCY” channel name when it is in emergency mode.

If you set to “off” by KPG-38D the transceiver shows se-

lected group/channel/status before entering to the emer-

gency mode however the transceiver is in an emergency

mode.

•Emergency Mode Type

Speaker mute on or off in the emergency mode.

•Emergency Type

Select an Emergency code format from DTMF, MSK, ANI

board or OFF (Disabled).

•Emergency DTMF ID

The Fleet number when you select DTMF in the emer-

gency type.

•Emergency Call Fleet

The emergency fleet number when you select MSK in

the emergency type.

•Emergency Call ID

The emergency DTMF ID code when you select MSK in

the above emergency type.

3-19. Radio Password (Keypad Model Only)

The radio password prevent unauthorized users opera-

tion. Every time the power on, transceiver is locked and

unusable until entering correct password.

Enter pre-programmed password by FPU and [#] key

causes the transceiver unlocked.

3-20. Data Password

The data password prevents unauthorized reading of the

programmed transceiver data by FPU. Enter pre-pro-

grammed password in FPU reading process. This password

also protects the clone.

Enter pre-programmed password by FPU and [#] key to

clone.

OPERATING FEATURES

TK-290

4. Group Features

You can use these features using the programming soft-

ware (KPG-38D).

4-1. “TOT”(Time-Out Timer)

The transceiver has the “TOT”. This parameter selects

the period of time users can continuously transmit.

When the selected period passes, the transceiver gener-

ates an warning tone and stops the transmission.

4-2. “TOT”Pre-Alert

The transceiver has “TOT” pre-alert timer. This param-

eter selects the time at which the transceiver generates

“TOT” pre-alert tone before “TOT” is expired.

“TOT” will be expired when the selected time passes

from a TOT pre-alert tone.

4-3. “TOT”Re-Key Time

The transceiver has “TOT” re-key timer. This timer is the

time you can not transmit after “TOT” exceeded. After

“TOT” re-key time expired you can transmit again.

4-4. “TOT”Reset Time

The transceiver has “TOT” reset timer. This timer is the

minimum wait time allowed during a transmission that will

reset the “TOT” count.

“TOT” reset time causes the “TOT” to continue even

after PTT is released unless the “TOT” reset timer has ex-

pired.

4-5. Group Delete/Add

The transceiver can set the delete/add in each group. If

“Delete” is selected, the transceiver does not scan the de-

leted group in multi group scan.

4-6. Battery Save

This is the automatic battery saver during a standby

mode operation. The receiver circuit is repeated on and off

to conserve the battery life.

4-7. Signalling

Signalling “AND/OR” sets the audio unmute condition

for any channel programmed with the option signalling (2-

Tone/DTMF).

AND : “AND” requires both the valid option signalling

and the programmed QT/DQT to be received for audio to

unmute (and initiate an option signalling decode alert).

OR : “OR” requires either the valid option signalling or

the programmed QT/DQT to be received for audio to

unmute (an option signalling decode alert is only initiated

if the proper option signalling is decoded).

OPERATING FEATURES

5. Channel Features

You can use these features using the programming soft-

ware (KPG-38D).

5-1. Option Signalling

The transceiver is programmable to the option signalling

(2-Tone decode program 1, 2-Tone decode program 2, 2-

Tone decode program 3, DTMF decode) to each channel. It

is useful to receive an individual call.

Receive format is selectable “AND” or “OR” with QT/

DQT for each group. The radio response of option signalling

is programmable “(Call) Alert tone” or “Transpond” for each

option signalling (2-Tone decode program 1, 2-Tone decode

program 2, 2-Tone decode program 3, DTMF).

5-2. PTT ID

PTT ID provides a DTMF ANI, MSK ANI or ANI board ID (if

installed) to be sent with every time PTT (connect ID at be-

ginning of transmission, disconnect ID at end of transmis-

sion, or both).

You can program PTT ID “on” or “off” for each channel.

The contents of ID are programmed for each transceiver.

5-3. Busy Channel Lockout

Transmission is inhibited when the channel is busy. It is

able to set this feature “Yes” or “No” for each channel.

5-4. Beat Shift

This is the feature that the microprocessor shifts its sys-

tem clock frequency slightly to prevent the receive interfer-

ence. This transceiver can program this feature “Yes” or

“No” for each channel.

5-5. TX Power

You can set the transmission power “High” or “Low” for

each channel. The each power setting is tuned at factory.

However, you can re-tune the power, using PC Tuning

Mode of KPG-38D.

5-6. Wide/Narrow

You can set the occupied band width mode “Wide” or

“Narrow” for each channel. It is useful for the operator to

use the transceiver on various sites.

5-7. Scan Delete/Add

Scanning “delete/add” is programmable for each chan-

nel. Set the currently selected channel required to include in

the scan sequence to “add”.

The operator can change the “delete/add” information

using the key programmed to “delete/add” function.

5-8. Compander

This function reduces the noise on the communications

channel used by the transceiver and improves reception.

If Wide/Narrow function is set to wide, this function

doesn't perform.

TK-290

6. Key Functions

You can use these features, using the programming soft-

ware (KPG-38D). Selector function is selectable channel se-

lect or group select.

The functions for Toggle switch are listed page 8 (Fig. 2).

Right position is active for programmed function on toggle

switch except “group select”.

The functions for the top key are listed page 8 (Fig.2).

Hold action and shift action are programmable.

The functions for side key are listed page 8 (Fig.2). Hold

action and shift action are programmable.

The functions for microphone key are listed page 8

(Fig.2). Hold action is programmable.

6-1. No Function

Sounds error operation beep, and no action will occur.

Use this function when the transceiver is required to be

more simple operated.

6-2. AUX.

This function can be programmed when the voice scram-

bler board is not installed.

If this key is pressed, “AUX” icon lights on the LCD and

AUX port which is inside of the transceiver turns to the high

level. If pressed again, the “AUX” icon goes off and the

AUX ports turns to the lower level.

6-3. Channel Down

If this key is pressed once, the channel number de-

creases by one step. If this key holds down for 500ms (ap-

proximate), the channel number decreases continuously.

This key works as the squelch level adjuster in a squelch

level adjust mode. This key works as the OST (operator se-

lectable tone) number selector in the OST mode. This key

works as the SCR (voice scrambler) code selector in the

voice scrambler code select mode.

6-4. Channel Up

If this key is pressed once, the channel number increases

by one step. If this key holds down for 500ms (approxi-

mate), channel number increases continuously.

This key works as the squelch level adjuster in squelch

level adjust mode. This key works as the OST (operator se-

lectable tone) number selector in the OST mode. This key

works as the SCR (voice scrambler) code selector in the

voice scrambler code select mode.

6-5. Channel Name

This key switches the LCD display between the group/

channel number and the group/channel name.

6-6. Delete/Add

This key switches the currently displayed channel be-

tween “Delete” and “Add”.

The “Add” channel contained in the scan sequence, and

“Delete” channel is not contained. In the scan mode, this

key switches the channel delete or add temporarily.

OPERATING FEATURES

Toggle PF Keys Speaker/

Function Name Selector Switch

Microphone

PF Keys

Aux 1✓✓✓

Channel Down ✓✓

Channel Name ✓✓

Channel Select ✓

Channel Up ✓✓

Delete/Add ✓✓

Emergency Call 2✓✓

Group Down ✓✓

Group Scan ✓

Group Select ✓✓

Group Up ✓✓

Home Channel ✓✓

Invert Display ✓✓✓

Key Lock ✓✓✓

Lamp ✓✓

Low Power ✓✓✓

Monitor ✓✓✓

Monitor Momentary ✓✓

No Function ✓✓✓

Operator Selectable ✓✓

Tone

Operator Selectable ✓

Priority 1

Operator Selectable ✓

Priority 2

Scan ✓✓✓

Scrambler 3✓✓✓

Shift ✓✓

SP Attenuation ✓

Squelch Level ✓✓

Squelch OFF ✓✓✓

Squelch Momentary ✓✓

Talk Around ✓✓✓

1 This function can be selected when the scrambler board has not

been installed.

2 This function can be selected when the ANI board has been in-

stalled.

3 This function can be selected when the scrambler board has

been installed.

Note : If “Shift” is pregrammed onto one of the PF keys or the

toggle switch, the remaining PF keys can be programmed with two

different functions. If “Shift” is programmed onto a PF key and the

toggle switch, an error will occur and the function will not operate.

Fig. 2 Programmable functions

TK-290

6-7. Group Down

If this key is pressed once, the group number decreases

by one step. If this key holds down for 500ms (approxi-

mate), the group number decreases continuously.

This key works as the squelch level adjuster in squelch

level adjust mode. This key works as the OST (operator se-

lectable tone) number selector in the OST mode. This key

works as the SCR (voice scrambler) code selector in the

voice scrambler code select mode.

6-8. Group Up

If this key is pressed once, the group number increases

by one step. If this key holds down for 500ms (approxi-

mate), the group number increases continuously.

This key works as the squelch level adjuster in the

squelch level adjust mode. This key works as the OST (op-

erator selectable tone) number selector in the OST mode.

This key works as the SCR (voice scrambler) code selector

in the voice scrambler code select mode.

6-9. Home Channel

Press this key once, the channel switches to the pre-pro-

grammed home channel. Press this key again, the channel

goes back to the previous channel.

6-10. Invert Display

Press this key once, the displayed the group/channel

number or group/channel name are inverted. Press this key

again, the display returns to the normal.

For the operator who does not change the display and

needs “Invert” only, refer “Invert Display” setting of op-

tional feature.

6-11. Key Lock

Pressing this key causes the transceiver to accept an en-

try of only the [Shift], [KeyLock], [PTT], [Emergency],

[LAMP], [Monitor], [Monitor Momentary], [Squelch Off],

[Squelch Momentary], [SP MIC Attenuation] keys, [Selector

switch], [Volume], [Toggle], [Lamp], [Moni], [Moni momen-

tary], [SQ off] and [SQ momentary].

“Lock” is used to prevent users from unexceptable key

press which might cause a transceiver malfunction. The dis-

play does not change while the key is being locked.

Switching the transceiver off and on or pressing Key Lock

again cancels the key lock. Key locked transceiver can still

receive. Pressing this key while scanning, keys are locked

but a scanning continues.

6-12. Lamp

Press this key, the transceiver illuminates the display and

keypad back lit approximate 5 seconds. Press this key

again, the transceiver stops the illuminating.

Pressing any key except the LAMP key while the illumi-

nated restarts the 5 second timer.

6-13. Low Power

Press this key, the transmission power of all channel

changes to Low. Press this key again, the transmission

power returns to programmed value.

6-14. Monitor

Monitor the channel before a transmission.

Press this key once, “MON” appears and unmutes

speaker if a carrier is present, regardless of the specified

signalling (including option signalling). Press this key again,

“MON” disappears and mutes speaker.

Press this key after the Option Signalling is matched, the

Option Signaling is reset and monitor is activated. DBD

(Dead Beat Disable) mode is not reset by this operation.

6-15. Monitor Momentary

While pressing this key, the monitor function (refer 6-14)

is activated. Release this key, the monitor function is de-

activated.

6-16. Operator Selectable Tone

This key switches the pre-set decode QT/DQT and en-

code QT/DQT to OST (Operator Selectable Tone) tone pair.

Press this key, the transceiver enters to OST select

mode. In this mode, the display shows “OFF” and the op-

erator can select one of the OST tone pair using the channel

up/down key or the group up/down key. The display shows

“TONE ✽ ✽” and tone pair No. ✽ ✽ is selected.

Press OST key again, the transceiver exits from the OST

select mode, and returns to the group/channel mode with

“OPT” icon. “OPT” icon means that the OST tone pair is

selected. OST tone pair number or OFF can be memorized

for each channel.

16 kinds of tone pair for OST can be programmed by

KPG-38D. OST is useful to access the repeater with same

radio frequency and different tone (QT/DQT).

6-17. Operator Selectable P1

If priority channel 1 is set as “Fixed” and “None” in the

scan information. The operator can select the priority chan-

nel 1, using this key (operator selectable fixed P1).

Press this key on normal channel, the channel becomes

to priority channel 1. Previous priority channel 1 returns to

the normal channel. Press this key on the priority channel 1,

the priority 1 will be lost (no priority 1).

6-18. Operator Selectable P2

If priority channel 2 is set as “Fixed” and “None” in the

scan information. The operator can select the priority chan-

nel 2, using this key (operator selectable fixed P2).

Press this key on the normal channel, the channel be-

comes to the priority channel 2. Previous priority channel 2

returns to the normal channel. Press this key on priority

channel 2, the priority 2 will be lost (no priority 2).

6-19. Scan

Press this key starts scanning. Pressing this key stops

scanning.

6-20. Shift

This key activates “Shift + [Key]” function. It is useful

when the numbers or more of the functions are necessary.

OPERATING FEATURES

TK-290

6-21. Squelch Level

The preset squelch level is varied in user mode (0 to 15).

Press the key programmed to “squelch level”, the trans-

ceiver enters to “squelch level adjust mode”.

The squelch level can be adjusted by group “up/down”

function key or channel “up/down” function key. Press the

key programmed to “squelch level” again, the adjusted

level is memorized and returns to the normal user mode.

6-22. Squelch Momentary

While pressing this key, the transceiver unmutes

speaker regardless of an existence of a carrier and “MON”

appears and busy “LED” lights on.

Release this key, the transceiver mutes the speaker and

“MON” disappears and busy “LED” lights off.

6-23. Squelch Off

Press this key, the transceiver unmutes speaker regard-

less of the existence of a carrier and “MON” appears and

busy “LED” lights.

Press this key again, the transceiver mutes the speaker

and “MON” disappears and busy “LED” lights off.

6-24. Talk Around

Press this key, the transceiver uses the receive fre-

quency and the tone for transmission.

The operator can call the other party directory (without

repeater). Press this key again, the talk around function

goes off.

6-25. Emergency Call

Press this key, the transceiver enters to an emergency

mode. In this mode, the channel is switched to the pro-

grammed emergency channel automatically and starts

transmission with an emergency ID code which is pro-

grammed to ANI board.

The display depends on “Emergency Channel Display”

setting.

6-26. SP Attenuation

Press this key once, the volume level of speaker-micro-

phone is attenuated. Press this key again, the volume level

of speaker-microphone returns to the previous level.

7. 2-Tone

Built-in 2-Tone decoder (decoder program 1, decoder pro-

gram 2, decoder program 3) is available for option signalling.

It is possible to use individual call or group call.

8. DTMF

Built-in DTMF encoder is available for dialing (Manual

dial, Auto-dial (9 memory), Re-dial (1 memory)) (Keypad

model only). Built-in DTMF decoder is available for option

signalling.

It is possible to use individual call, group call, DBD (Dead

Beat Disable).

9. Data Programming (PC Mode)

9-1. Preparation and Connection

TK-290 transceiver is programmed by using a personal

computer, programming interface cable KPG-36, and pro-

gramming software KPG-38D.

The programming software can be used with an IBM-PC

or compatible machine. Figure 3 shows the setup for pro-

gramming.

9-2. Programming Interface Cable KPG-36 Description

The KPG-36 is required to interface TK-290 to the com-

puter. It has a circuit in its D-sub 25pin connector case that

converts RS-232C logic level to TTL level.

KPG-36 is used to connect between TK-290 universal

connector and RS-232C serial port of computer.

9-3. Programming Software KPG-38D Description

KPG-38D is the programming software for TK-290 sup-

plied on a 3.5" floppy disk. This software runs under MS-

DOS version 3.1 or later on an IBM-PC/XT, AT, or PS2 or

compatible machine.

The data can be input to or read from TK-290 and edited

on the screen. The programmed or edited data can be

printed out. It is also possible to tune the transceiver.

We recommend that install KPG-38D for example to

harddisk first then use it.

KPG-38D instruction manual part No. : B62-0814-XX.

Fig. 3

KPG-36

IBM-PC

KPG-38D

OPERATING FEATURES

TK-290

1. Mode

PC mode PC programming mode

PC test mode

PC tuning mode

Self programming mode

Function setting mode

Group setting mode

Channel setting mode

Clone master mode

Panel test mode LCD all lamp mode

Panel tuning mode

Clear function

Firmware programming mode

User mode

3. Self Programming

Write mode for frequency data and signalling etc. Mainly

used by the person maintaining the user equipment.

3-1. Enter to the self programming mode

Turn the power switch on, with the lead wire with plug

PF (8 pin) shorted to the E (10 pin) lead (Figure 5), or delete

R491 (SELF, Figure 6) in the TX-RX unit and turn the power

switch on while pressing the [Side 1] and [Side 2] keys.

Note :

This mode (self programming mode) cannot be set when

it has been disabled with the FPU.

•Additional Modification of the Plug

It‘s available to enter the self programming mode by

modifying the pattern of lead wire as following.

REALIGNMENT

Mode Function

User mode Customer use this mode

PC mode Communication between the radio

and PC (IBM compatible).

It requires the KPG-38D

PC programming mode Frequency, signalling and features

write to the radio and read from

the radio.

PC test mode Check the radio using the PC.

This feature is included in the FPU.

Self programming mode Frequency, signalling and features

write to the radio.

Panel test mode Dealer use to check the fundamen-

(Refer to Adjustment) tal characteristics.

Firmware programming mode

Re-write the firmware of the flash

ROM.

2. How to Enter Each Mode

Mode Operation

User mode Power on

PC mode Power on begins the USER MODE.

Self programming mode Hold down the [Side 1] key and the

[Side 2] key, turn the radio power

on.

Panel test mode Hold down the [Side 2] key and

[PTT], turn the radio power on, and

release [PTT] first.

Firmware programming mode

Held down the [Side 2] key and

[PTT], turn the radio power on, and

release [Side 2] key first.

Fig. 4

11: GREEN (5M)

TUBE

SCREW

8: YELLOW (PF SW)

2: RED (RX AF OUTPUT)

3: BLACK (RX AF OUTPUT)

10: BROWN (GND)

6: BROWN (MIC GND)

5: WHITE (MIC INPUT)

7: BLUE (PTT SW) GND →ON

Shorted

Lead wire with plug

(E30-3287-08)

Fig. 5

Cut the pattern between

SSW and GND.

CN2

TK-290

When enter the self programming mode, “FUNC” ap-

pears after “SEL” is displayed for half a second.

Selecting any of Channel setting, Group setting, Function

setting, or Clone master with the [Top 1] [Top 2] keys and

then pressing [PTT] sets the Setting mode for that time.

Key operations in Self programming mode are as follows.

[Selector switch] : Not used

[PTT] : Functions as a RUN or Execute key

[Top 1] : Use as a Down key

[Top 2] : Use as an Up key

[Side 1] : Use for select channel steps in Chan-

nel setting mode, or switching for

QT/DQT.

[Side 2] : Use as a cancel key

[Orange] : Add or delete frequencies in Channel

setting mode

[Toggle] : Flipping this to the right while in

Channel setting mode, shifts to MHz

steps.

REALIGNMENT

3-2. Channel Setting Mode

Set data for each channel while in this mode. After first

entering Self programming mode, select the “CHAN” dis-

play with [Top 1] [Top 2] and press [PTT] to set Channel Set-

ting mode. Once in Channel Setting mode, select the group

that needs setting with the [Top 1] [Top 2] keys and press

[PTT]. Next select the channel for setting with the [Top 1]

[Top 2] keys and press [PTT]. The setting items and setting

data will then appear so reset the data with the [Top 1]

[Top 2] keys and press [PTT]. When finished, the display

shifts to the next setting item. After finished setting all

items press [PTT] to return to Group selection. Changes in

the frequency CH steps and the QT/DQT steps can be made

in [Side 1].

No. Function name Display Remarks

Select 1.–1 during 1–160~160–1

Group/Channel

group selection

1–1. during

channel selection

1 RX frequency R150.0125 Receive frequency

2 RX signalling RX 023N Receive QT/DQT

(Dot on right edge is

lit up during 1 step

changes)

3 TX frequency T150.0125 Transmit frequency

4 TX signalling TX 250.3 Transmit QT/DQT

(Dot on right edge is

lit up during 1 step

changes)

5 Option signalling 2ToneA OFF, DTMF, 2ToneA,

2ToneB, 2ToneC

6 DEL/ADD D/A ADD Delete, Add

7 Wide/Narrow WIDE Wide. Narrow

8 PTT ID ID OFF OFF, ON

9 TX power POW HI High, Low

Busy channel lockout

BCL OFF OFF, ON

11 Beat shift SFT OFF OFF, ON

•Channel step display

Attach the lead wire with plug

[Side 1] + [Side 2] + Power on “SEL”

“FUNC”

“GROUP”

“CHAN”

“CLONE”

[PTT]

[Top 1]

[Top 2]

[Top 1]

[Top 2]

[Top 1]

[Top 2]

[PTT]

Fig. 6

X57-5390-10

Component side

R491

SELF

TP5

TP4

5kHz step

6.25kHz step

7.5kHz step

2.5kHz step

1.25kHz step

TK-290

•Operation

1. Select the setting value with the [Top 1] [Top 2] keys.

2. Press the [PTT] and the selected value is backed up and

operation shifts to the next item for setting.

3. Press [Side 2] on the Group selection screen in order to

return to Self programming mode.

•Note

1. Different sample displays are shown.

2. Setting item No.s are displayed with a 7-segment 2-digit

figure on the LCD.

3. Self programming mode cannot be set when set to

Disaable with the FPU.

4. A red LED lights up during TX frequency and TX signal-

ling.

5. Press [Orange] on the TX, RX frequencies setting screen

in order to clear in the channel frequencies data.

6. Press [Orange] on the signalling setting screen in order to

change or off the signalling function.

7. Flipping [Toggle] to the right during setting of RX, TX fre-

quencies and performing Up/Down operation allows fre-

quencies to be changed in MHz steps.

8. The RX and TX frequencies can be entered with the num-

ber pad keys.

•Flow Chart

3-3. Group Setting Mode

Set data for each Group while in this mode. After first

entering Self programming mode, select the “GROUP” dis-

play with [Top 1] [Top 2] and press [PTT] to set Group Set-

ting mode. Once in Group Setting mode, select the group

that needs setting with the [Top 1] [Top 2] keys and press

[PTT]. Next select the channel for setting with the [Top 1]

[Top 2] keys and press [PTT]. The setting items and setting

data will then appear so reset the data with the [Top 1]

[Top 2] keys and press [PTT]. When finished, the display

shifts to the next setting item. After finished setting all

items press [PTT] to return to next Group selection.

No. Function name Display Remarks

Select Group GRP 1 1~160

1 Battery save BATT L OFF, Short, Mid, Long

2 Time out timer TOT 60

OFF, 30s~300s (30s step)

3 TOT pre alert TOT.P 10 OFF, 1s~10s (1s step)

4 TOT rekey time TOT.K 2 OFF, 1s~60s (1s setp)

5 TOT reset time TOT.S 2 OFF, 1s~15s (1s step)

6 Group Delete/Add D/A ADD Delete, Add

7 Signalling SIG AND AND, OR

•Operation

1. Select the setting value with the [Top 1] [Top 2] keys.

2. Press the [PTT] and the selected value is backed up and

operation shifts to the next item for setting.

3. Press [Side 2] on the Group selection screen in order to

return to the Self programming mode initial display.

•Note

1. Different sample displays are shown.

2. Setting item No.s are displayed with a 7-segment 2-digit

figure on the LCD.

3. Self programming mode cannot be set when set to Dis-

able with the FPU.

•Flow Chart

Self programming mode

Channel setting mode

Group selection

Channel selection

1. RX frequency

2. RX signalling

3. TX frequency

4. TX signalling

5. Option signalling

6. Scan Delete/Add

7. Wide/Narrow

8. PTT ID on/off

9. TX power Hi/Low

10. Busy channel lockout on/off

11. Beat shift on/off

[Top 1] [Top 2]

[PTT]

[Side 2]

Orange Orange

Orange

Orange Orange

OFF

DQT I DQT N

Orange Orange

Orange

Orange Orange

OFF

DQT I DQT N

REALIGNMENT

Self programming mode

Group setting mode

Group selection

1. Battery save

2. Time out timer (TOT)

3. TOT pre-alert

4. TOT rekey time

5. TOT reset time

6. Scan group Delete/Add

7. Signalling AND/OR

[Top 1] [Top 2]

[PTT]

[Side 2]

TK-290

3-4. Function Setting Mode

This mode allows making function settings for the trans-

ceiver. After first entering Self programming mode, select

“FUNC” display with [Top 1] [Top 2] and then press [PTT] to

set this mode. Function setting items are listed below.

No. Function name Display Remarks

1 Power on tone POW.T 15 (or C) Continuas, 0~31

2 Control tone CON.T 15 (or C) Continuas, 0~31

3 Warning tone WAR.T 15 (or C) Continuas, 0~31

4 Alert tone ALR.T 15 (or C) Continuas, 0~31

Minimum volume

MIN.V 8 0~31

6 Battery warning BATT ON Disable, Enable

7 Busy LED B.LED ON OFF, ON

8 TX LED T.LED ON OFF, ON

9 Invert Display LCD ON Disabel, Enable

10 Priority 1 P1 NONE

None, Selected, Fixed

11 Priority 1 group 1.–1 1–1~10–16

Priority 1 channel 1–1.

(Priority 1= In fixed)

13 Priority 2 P2 NONE

None, Selected, Fixed

14 Priority 2 group 1.–1 1–1~10–16

Priority 2 channel 1–1.

(Priority 2= In fixed)

16 Revert channel REVT 1 1~8

1 : Selected

2 : Last called

3 : Last used

4 : Sel+Talk back

5 : Priority 1

6 :

Priority 1+Talk back

7 : Priority 2

8 :

Priority 2+Talk back

17 Squelch level SQ.LV 15 0~15

•Operation

1. Select the setting value with the [Top 1] [Top 2] keys.

2. Press the [PTT] and the selected value is backed up and

operation shifts to the next item for setting.

3. Press [Side 2] on the Group selection screen in order to

return to the Self programming mode initial display.

•Note

1. Different sample displays are shown.

2. Setting item No.s are displayed with a 7-segment 2-digit

figure on the LCD.

3. Self programming mode cannot be set when set to Dis-

able with the FPU.

REALIGNMENT

•Flow Chart

Self programming mode

Function setting mode

1. Power on tone

2. Control tone

3. Warning tone

4. Alert tone

5. Minimum volume

6. Battery warning on/off

7. Busy LED on/off

8. TX LED on/off

[Top 1] [Top 2]

[PTT]

[Side 2]

9. Invert display on/off

10. Priority 1 setting

11. Priority 1 group selection

12. Priority 1 channel selection

13. Priority 2 setting

14. Priority 2 group selection

15. Priority 2 channel selection

16. Revert channel

17. Squelch level

TK-290

3-5. Clone Mode

1. Connect the cloning interface cable between the master

side transceiver (source) and slave side transceiver

(clone) as shown in the figure.

REALIGNMENT

•Group Clone

1. To clone the transceiver group data and channel data

within the group, as well as group alphanumeric data, use

the [Top 1] key or [Top 2] key to switch the display on the

master side transceiver from “A CLONE” to “G

CLONE”.

2. Press [PTT] to show the group cloning selection.

3. Select the group with the [Top 1] or [Top 2] keys.

4. Press [PTT] to show the slave side group cloning selec-

tion.

5. Select the group with the [Top 1] or [Top 2] keys.

6. Press the master side [PTT] to start cloning.

Cloning interface cable

Part No. E30-3325-05

[PTT]

A CLONE END

Red lamp flashes

[PTT]

[Top 1]

[Top 2]

[Top 1] [Top 2]

SEL CHAN CLONE

A CLONE

G CLONE

2. Set the master side transceiver to Self programming

mode, and the transceiver display to “CLONE” with the

[Top 1] key or [Top 2] key and press [PTT].

3. Set the power switch on the slave side transceiver to

ON.

4. The red LED on the master side transceiver flashes when

cloning starts and an “END” message appears when

cloning ends.

5. The green LED on the slave side transceiver flashes.

6. When a problem occurs during cloning, an “ERROR”

message appears on the master side transceiver.

7. Pressing the [Side 2] key sets clone mode.

Note :

The master transceiver copies only to type matched

slave.

•All Clone

1. Press [PTT] on the master side transceiver to start clon-

ing of all data except for the transceiver model type and

alignment data.

•Flow Chart

[Top 1] [Top 2]

A CLONE G CLONE

[PTT] [PTT]

G CLONE GRP 1M GRP 1S

[PTT]

GRP 1S END

Red lamp flashes

Group clone mode

"Master" group selection

"Slave" group selection

All clone mode

[PTT]

[Top 1]

[Top 2]

[PTT]

[PTT] [PTT]

[PTT]

[ ] [ ] ··· [#]

[PTT]

[Side 2]

[Top 1] [Top 2]

[Side 2]

[Side 2][Side 2]

[Side 2]

END

All clone/group clone selection

Password input

Clone lock

Self programming mode

Clone master mode

Only the keypad model and

set to password with the FPU.

TK-290

4. Firmware Programming Mode

4-1. Preface

Flash memory is mounted on the TK-290. This allows the

TK-290 to be upgraded when new features are released in

the future. (For details on how to obtain the firmware, con-

tact Customer Service.)

4-2. Connection Procedure

Connect the TK-290 to the personal computer (IBM PC or

compatible) with the interface cable (KPG-36). (Connection

is the same as in the PC Mode.)

4-3. Programming

1. Start up the programming software (KPG-38D), select

“firmware program” in the “Program” item, and press

the Return key on the personal computer. This starts up

the firmware programmer.

2. The top screen is displayed. Press any key to advance to

the next screen.

3. Set the communications speed (normally, 38400 bps)

and communications port in the Setup item.

4. Set the firmware to be updated by File select.

5. Held down the [Side 2] and [PTT]. Turn the TK-290 power

on, and release [Side 2] first. Until the display change to

“PROGRAM”.

6. Check the connection between the TK-290 and the per-

sonal computer, and make sure that the TK-290 is in the

Program mode.

7. Press F10 on the personal computer. A window opens

on the display to indicate progress of writing. When the

TK-290 starts to receive data, “PG” is appeared on 2 digit

sub display.

8. If writing ends successfully, the red LED on the TK-290

lights and the checksum is displayed.

9. If you want to continue programming other TK-290s, re-

peat steps 5 to 8.

Notes :

• To start the Firmware Programmer from KPG-38D, the

Fpro path must be set up by KPG-38D setup.

• This mode cannot be entered if the Main Program mode

is set to Disable in the Programming software (KPG-38D).

REALIGNMENT

4-4. Function

1. If you press the [Top 2] switch while “PROGRAM” is dis-

played, the checksum is displayed. If you press the

[Top 1] switch while the checksum is displayed, “PRO-

GRAM” is redisplayed.

2. If you press the [Top 1] switch while “PROGRAM” is dis-

played, 1 dot light (“M.”) to indicate that the write speed

is low-speed (19200 bps). If you press the [Top 1] switch

again while low-speed (19200 bps), 2 dot lights (“.M.”) to

indicate, and the write speed becomes the high-speed

mode (38400 bps).

The communication speed changes 19200 bps, 38400

bps, 57600 bps (3 dots), and 115200 bps (4 dots) every

time you press [PTT] and [Top 1].

Note :

Normally, write in the high-speed mode.

When the Flash ROM is replaced, the initial communica-

tion speed for writing becomes 115200 bps.

5. Panel Test Mode

Setting method refer to ADJUSTMENT.

TK-290

1. Overview

The KENWOOD model TK-290 is a VHF/FM hand-held

transceiver designed to operate in the frequency range of

136 to 174MHz, the unit consists of a receiver, a transmit-

ter, a phase-locked loop (PLL) frequency synthesizer, power

supply circuits, a control unit.

2. Circuit Configuration by Frequency

The receiver is a double-conversion superheterodyne

with a first intermediate frequency (IF) of 44.85MHz and a

second IF of 455kHz. Incoming a signals from the antenna

are mixed with the local signal from the PLL to produce the

first IF of 44.85MHz.

This is then mixed with the 45.305MHz second local os-

cillator output to produce the 455kHz second IF. This is de-

tected to give the demodulated signal.

The transmit signal frequency is generated by the PLL

VCO, and modulated by the signal from the microphone. It

is then amplified and sent to the antenna.

3. Receiver System

3-1. Front-end RF amplifier

The signal are then passed through an antenna matching

coil, where the high-frequency components are amplified by

a GaAs FET (Q200). The signals are then fed into band-pass

filter that uses varactor diode tuning to reject unwanted sig-

nal components, and is fed to the 1st mixer.

3-2. First mixer

The 1st mixer uses the GaAs IC (IC200). The 1st mixer

mixes the signal with the 1st local oscillator frequency from

the VCO, and converts it to the 1st IF (44.85MHz).

The signal then passes through monolithic crystal filter

(XF301) to remove unnecessary nearby frequency compo-

nents. The signal from the MCF is used as the 1st IF signal.

3-3. IF amplifier

The 1st IF signal is amplified (Q302) and fed into IC300 in

the FM IF IC. The IF signal is then mixed with the 2nd local

oscillator frequency of 45.305MHz to generate the 2nd IF of

455kHz. The 455kHz signal is then passed through a ce-

ramic filter (CF300, CF301 ; Wide, CF302, CF303 ; Narrow)

and fed back into IC300 for additional amplification.

ANT

TX/RX

: 136~174MHz

ANT

AMP

1st MIX MCF

44.85MHz

XF301

455kHz

CF300,301

FM IF

SYSTEM

AMP SP

45.305MHz

180.85~218.85MHz

136~174MHz

PLL

VCO MIC

AMP MIC

Fig. 1 Frequency configuration

T/R

Q200

RF AMP

L202

BPF

L205

BPF

L201

BPF

L206

BPF

IC200

1st MIX

D602

D603

MCF

XF301

Q302

IF AMP

IC300

FM IF SYSTEM

X300

45.305

MHz

CF300,301

Wide

CF302,303

Narrow

Fig. 2 Receiver section

Item Rating

Nominal center frequency 44.85MHz

Pass band width ±5~7kHz at 3dB

Attenuation band width ±25kHz or less at 30dB

Ripple 1.0dB or less

Insertion loss 4dB or less

Guaranteed attenuation 80dB or more at fo±910kHz

40dB or more within fo±1MHz

Terminating impedance 350Ω/ 4.5pF

Table 1 Crystal filter XF301 (L71-0588-05)

CIRCUIT DESCRIPTION

TK-290

3-4. Wide/Narrow changeover circuit

Narrow and Wide settings can be made for each channel

by switching the ceramic filters CF300, CF301 (Wide),

CF302, CF303 (Narrow).

The WIDE (high level) and NARROW (low level) data is

output from IC400 (I/O port expansion) pin 4.

When a WIDE (high level) data is received, Q303 turn off

and Q304 turn on. When a NARROW (low level) data is re-

ceived, Q303 turn on and Q304 turn off. D302, D303 are

switched to ceramic filters when a high/low level data is re-

ceived.

Q305 turns on/off with the Wide/Narrow data and the

IC300 detector output level is changed to maintain a con-

stant output level during wide or narrow signals.

Q303

Q304 D302

R315

R317

C330

C331

R325

D303

R328

W/N

W/N “H”: Wide

“L”: Narrow

MXO

IFI

MXI

IFO

QAD

AFO

CD300

C316

R322

R326

R320

Q305

IC300

FM IF SYSTEM

Q302

C321

R324

C311

CF300 CF301

CF302 CF303

R318

Fig. 3 Wide/Narrow changeover circuit

•Control unit

The audio mute signal (AMP SW) from the microproces-

sor becomes Low in the standby and Q5, Q6 which are

power supply circuit for IC1 turn off. When the audio is out-

put, AMP SW becomes High to turn Q5, Q6 on, and voltage

is supplied to power terminal VP of IC1.

Speaker switching is done from IC403 (TX-RX unit) by INT

AFC or EXT AFC. First, the logic level at the speakers

switching terminal (SSW) on the universal connector is input

to the microprocessor (IC406 TX-RX unit). The microproces-

sor then outputs data to IC403 based on this input.

When there is no SP-MIC installed, this logic level is high.

When the INT AFC is high, the EXT AFC goes low, so the AF

signal is only input to the amplifier for the internal speaker

(INT SP) of IC1. However, when a SP-MIC has been in-

stalled, this logic level is low, so the INT AFC goes low and

the EXT AFC goes high. So that the AF signal is input only to

amplifier for the external speaker (EXT SP) of IC1.

IC300

MIX, DET, IF SW

IC301

IC601 (2/2)

AF AMP

CF300

CF301

CF302

CF303

DE-

EMP MUTE

EXP

HPF LPF HPF BEF

IC607 21

VOL

IC603 IC604 (2/2)

AF AMP

SWSW

Q15

INT AFC

EXT AFC

INT.SP

EXT.SP

AMP SW

2nd local

OSC

X300

IC1

Fig. 4 Audio amplifier circuit

3-6. Squelch circuit

It amplifies the demodulated noise signal from FM IC

(IC300) after filtering through BPF circuit. Then, the ampli-

fied signal is coverted to DC signal by the detection circuit.

The coverted signal is feeded through the microprocessor

(IC 406) and the voltage level is detected by ADC (A/D con-

verter) to control the squelch circuit.

Fig. 5 Squelch circuit

CIRCUIT DESCRIPTION

IC300

OUT

NOISE

AMP

Q301

BUSY

CPU

OUTPUT

EXPANDER

IC406

IC403

AMP SW

INT AFC

EXT AFC

DET

D300

NOISE

AMP

DET

OUT

3-5. Audio amplifier circuit

•TX-RX unit

The demodulated signal from IC300 goes through IC301,

and is amplified by IC601 (2/2), high-pass filtered, low-pass

filtered, high-pass filtered, band-eliminate filtered, and de-

emphasized by IC607.

The signal then goes through an electronic volume con-

trol (IC603), an AF amplifier IC604 (2/2), and an AF switch

(Q8 is on and Q7 is on of the control unit), and is routed to

audio power amplifier (IC1 of the control unit), where it is

amplified and output to the internal speaker.

TK-290

4. Transmitter System

4-1. Microphone amplifier

The signal from IC3 (control unit) goes through the mute

switch (Q403).

When the SP-MIC is not attached, the microphone

switching terminal (MSW) on the universal connector be-

comes High, and mute switch (Q403) is turned on. When

the SP-MIC is attached, MSW is connected to GND at inside

of SP-MIC. For this reason, Q403 is turned off, the internal

microphone is muted, and only the input of the external mi-

crophone is supplied to the microphone amplifier of the TX-

RX unit.

The signal from microphone passes through the limiter

circuit in D601, and through the high-pass filter, the ALC cir-

cuit, the low-pass filter, the high-pass filter, and pre-empha-

sis/IDC circuit in IC607. When encoding DTMF, mute

switch (Q601) is turned off for muting the microphone input

signal.

The signal passes through the D/A converter (IC603) for

the maximum deviation adjustment, and enters the sum-

ming amplifier consisting of IC605 (1/2), and is mixed with

the low speed data from the CPU (IC406).

The output signal from the summing amplifier goes to

the VCO modulation input.

The other output signal from the summing amplifier

passes through the D/A converter (IC603) again for the BAL

adjustment, and the buffer amplifier (IC604 1/2), and goes to

the VCXO modulation input.

4-2. Noise cancelling microphone circuit

The two signals from INT MIC (Main & Sub) are input to

the positive (+) input (Sub) and to the negative (–) input

(Main) of the IC3. If the same signal is input to both Main

and Sub, the Main signal is canceled at the output of IC3 (pin

7). In other words, noise from nearby sources not directly

connected to the transceiver enters the Main and Sub in-

puts at the same signal and is therefore canceled out.

When a signal is only input to Main and there is no signal

at Sub, the Main signal is output as is, from IC3 (pin 7). In

other words, only the voice audio of the operator in ex-

tremely close proximity to the Main MIC is input to Main so

that the signal is output as is from IC3 (pin 7). Also, when

the “N/C” switch is set to “L”, transistor Q14 turns off so

Sub microphone turns off and operation is the same as

above.

12 HPF LPF HPF IDC

PRE

EMP

ALC COMP

LIMIT

N/C

AMP MIC

Q403

IC3

(CONT)

D601

MIC

MAIN

SUB

EXT.

MIC

Q404

MSW

IC607 15 16 18 19

Q601

MM TONE

D/A

IC603

IC604

(1/2)

I4 O4

I3 O3

LSD

IC605 (1/2)

SUM

AMP

BUFF

AMP VCXO

VCO

IC10

4-3. Drive and Final amplifier

The signal from the T/R switch (D602 is on) is amplified

by the pre-drive (Q6) and drive amplifier (Q8) to 20mW. The

output of the drive amplifier is amplified by the RF power

amplifier (IC801) to 5W (1W when the power is low).

The RF power amplifier consists of two stages MOS FET

transistor. The output of the RF power amplifier is then

passed through the Transmit-Receive (TX-RX) antenna

switching (D10 is on) and the harmonic filter (LPF) and the

Internal-External (INT-EXT) antennal switching (in the univer-

sal connector) and applied to the antenna terminal.

From

T/R SW

(D602)

Pre-

DRIVE

AMP

DRIVE

AMP

POWER

AMP

TX-RX

ANT

LPF

EXT-INT

ANT

In the

universal

connector

ANT

ON→EXT

Q6 Q8 IC801 D10

VDD VGG

R35

R37

R39

IC7

(1/2)

IC7

(2/2)

REF

VOL

(IC3)

Q13

Fig. 7 Drive and final amplifier and APC circuits

Fig. 6 Microphoen circuit

4-4. Internal-External (INT-EXT) antenna switching

The INT-EXT antenna switch housed inside the universal

connector only switches to the EXT ANT side when an an-

tenna speaker-microphone has been installed.

This INT-EXT antenna switch works mechanically and

switches based on the operation shown in Figure 8.

OFF

From

LPF

INT

ANT

EXT ANT

From

LPF

INT

ANT

EXT ANT

Switch OFF

↓

Internal

antenna

Switch ON

↓

External

antenna

Fig. 8 Internal-External

antenna switching

CIRCUIT DESCRIPTION

Other manuals for TK-290

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Kenwood TK-290 User manual