Kirisun TP620 User manual

TP620 Service Manual

TP620 Service Manual
Contents
1. Overview...................................................................................................................................................1
1.1. Scope...............................................................................................................................................................1
1.2. Safety Precaution.............................................................................................................................................1
2. Introduction..............................................................................................................................................2
2.1. External Views and Functional Keys................................................................................................................2
2.2. LED Indicator ...................................................................................................................................................2
3. Circuit Description..................................................................................................................................3
3.1. Tx/Rx Signal Procedure...................................................................................................................................3
3.1.1. Tx Circuit .......................................................................................................................................................3
3.1.2. Rx Circuit.......................................................................................................................................................4
3.1.3. Frequency Synthesizer Circuit ......................................................................................................................6
3.2. Power Section..................................................................................................................................................7
4. Function Description and Parameter Settings.....................................................................................8
4.1. Conventional Functions ...................................................................................................................................8
4.2. Function Parameter Settings ...........................................................................................................................8
5. Assemble and Disassemble Instructions........................................................................................... 11
5.1. Attaching and Detaching the Battery .............................................................................................................11
5.2. Attaching the antenna....................................................................................................................................12
5.3. Attaching the Speaker /Microphone...............................................................................................................13
5.4. Attaching the Belt Clip....................................................................................................................................13
5.5. Separating the Shell from the Chassis ..........................................................................................................13
5.6. Separating the Aluminum Shell from the Main Board....................................................................................14
5.7. Exploded View ...............................................................................................................................................15
6. Adjustment and Test.............................................................................................................................17
6.1. Components for Adjustment...........................................................................................................................17
6.2. Adjustment Test Method ................................................................................................................................17
6.2.1. Frequency Description ................................................................................................................................17
6.2.2. Test Tools ....................................................................................................................................................18
6.2.3. Tx Test and Modulation...............................................................................................................................18
6.2.4. Rx Test and Modulation...............................................................................................................................20
7. Technical Functions and Specifications.............................................................................................21
8. Maintenance and Test Equipment.......................................................................................................23
9. Troubleshooting....................................................................................................................................24
Appendix .......................................................................................................................................................25
List 1 Material List (Electronic Section 400-470MHz).............................................................................................25
List 2 Material List (Electronic Section 136-174MHz).............................................................................................35
List 3 Material List (structure material)....................................................................................................................46
Figure 1 TP620 Main Board Top Side PCB View(400-470MHz) ............................................................................48
Figure 2 TP620 Main Board Bottom Side PCB View(400-470MHz).......................................................................48
Figure 3 TP620 Main Board Top Side PCB View(136-174MHz) ............................................................................49
Figure 4 TP620 Main Board Bottom Side PCB View(136-174MHz).......................................................................49
Figure 5 TP620 Mainboard Schematic Diagram(400-470MHz) .............................................................................50
Figure 6 TP620 Mainboard Schematic Diagram(134-174MHz) .............................................................................56
I

TP620 Service Manual
1.Overview
1.1.Scope
This manual applies to the service and maintenance of TP620 digital portable radios, and it is intended for
use only by engineers and professional technicians trained by Kirisun. Data changes in this manual may
occur with the improvement of technology. To get the latest technology information, please contact us or
your local dealer.
Please read this manual before repairing the radio.
1.2.Safety Precaution
Electromagnetic Radiation
Radios generate and radiate electromagnetic energy. The security design of TP620 radio’s
electromagnetic radiation on human meets national and international standards. To ensure radio’s optimal
performance and safe electromagnetic radiation on human, please keep the radio vertical to the ground
and 2-5 cm away from your mouth.
Electromagnetic Interference
To avoid electromagnetic interference, please turn off the radio wherever there are clear warnings, e.g.
hospitals, health care centers, airports, where radios must be turned off.
Explosive and Harmful Gases
The radio should be turned off in areas with explosives and harmful gases, e.g. lower deck of the hull, fuel
and chemical storage facilities, area where the air contains chemicals, particles, dust or metal dust.
Please turn off the radio when close to blasting area and electric blasting detonators.
Replacing or charging batteries in potentially explosive atmosphere is prohibited.
Antenna Damage
Do not use radios when the antenna is damaged. Damaged antenna may cause mild burning to human
skin.
Replacing Components
When replacing components, please be aware of the model. Do not arbitrarily replace any components
that do not match Kirisun’s requirement.
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TP620 Service Manual
2.Introduction
2.1.External Views and Functional Keys
No. Part Name No Part Name
1 LED Indicator 2 Power/Volume Switch
3 Channel Switch 4 PTT(Push-To-Talk)
5 Side Key 1(Programmable Key) 6 Side Key 2(Programmable Key)
7 Top Key (Programmable Key) 8 Speaker/Microphone Interface
2.2.LED Indicator
•The LED glows red: The radio is transmitting.
•The LED glows green: The radio is receiving (voice mail, message, data) oractivities on the channel are
detected.
•The LED flashes red: Low battery.
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3.Circuit Description
3.1.Tx/Rx Signal Procedure
Figure 3-1 RF Schematic Diagram
ANT
LPF
RF AMP
Q505
MCF
IF AMP
Q507
GT3136
450K
AF AMPAF PA
SPK
D501 D503
D504
XF501
49.95MHz
U102 NJM2902
IC101 TDA8547
TX/RX
SW
BPF
BPF
MIXER
CF501 450H
16.8MHz
TCXO
16.8MHz
To 50.4MHz
Q605
X601
Q509
450_IF AMP
CODEC
U201
HR_C5000
Q506 3SK318
PLL
2SK72310
Loop
Filter
TX VCO
RX VCO
Buffer PA
Pre-driver PA
driver PA
Final
Q504 2SC3356 Q503 2SC3356 Q502 RD01 Q501 RD07
MIC AF
AMP CODEC
MOD_I
MOD_Q
U103
NJM2100
3.1.1.Tx Circuit
Figure 3-2 Tx Circuit Diagram
ANT
LPF
D501 D503
D504
TX/RX
SW
16.8MHz
TCXO
X601
U201
HR_C5000
PLL
2SK72310
Loop
Filter
TX VCO
Buffer PA
Pre-driver PA
driver PA Final
Q504 2SC3356 Q503 2SC3356 Q502 RD01 Q501 RD07
MIC
AF
AMP CODEC
MOD_I
MOD_Q
U103
NJM2100
BATT+
APC
APC
U502
Tx circuit mainly includes four parts below:
•RF Power Amplifier Circuit
The carrier signal generated by VCO will be modulated and preliminarily amplified before entering Tx
circuit. The signal will first pass through a Π-type pure resistance attenuator R536 R537 R538 to realize
the level isolation between the power amplifier circuit and Tx VCO. Then the modulation signal enters the
first pre-drive amplifier (Q504) for preliminary amplification, which generates a certain isolation between
the first and second amplifier; The amplified signal will then enter the next pre- drive amplifier (Q503 and
drive amplifier (Q502 RD01)) for further power amplification so as to ensure that enough drive power
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TP620 Service Manual
signal can be offered to the last power amplifier (Q501 RD07) for final power amplification. After being
processed by a set of amplifiers at several levels, the Tx signal will complete the output impedance match
through a microstrip line at the output terminal of the last power amplifier, through which the output power
loss caused by impedance mismatch can be avoided. The Tx signal will then pass the Rx/Tx switcher and
enter the LPF.
•Low Pass Filter Circuit for Harmonic Suppression
Low pass filter which suppresses harmonic wave is a high level low pass filter consisting of capacitor and
inductor with concentrated parameters. The out-of-band harmonic wave and spurious signal can be
further suppressed on the condition that the certain in-band fluctuation is satisfied through this filter.
•Auto Power Control Circuit ( APC)
The drain current from the drive power amplifier and end-level power amplifier passes the sampling
resistors (R559 R560 R561) and the subtraction circuit which consists of the first operational amplifier to
realize the transformation from current to voltage. The voltage will be compared with the PAC control
voltage value output from DAC (U301 pin 29) at the second operational amplifier, and the output deviation
voltage will change the Tx power strength by controlling the grid bias voltage of power amplifier
tube(including drive level and end level).
•Audio Processing
The microphone converts the speech signal to speech electric signal, and the signal will be amplified by
U103 before being input intoADC of codec (U201 HR_C5000) for sampling, it will then be output into DSP
after audio being digitally processed, and sent to DAC for modulation signal conversion, the modulation
signal will be separated into path I and Q for modulating VCO, TCXO.
3.1.2.Rx Circuit
Figure 3-3 Rx Circuit Diagram
ANT
LPF
RF AMP
Q505
MCF
IF AMP
Q507
GT3136
450K
AF AMPAF PA
SPK
D501 D503
D504
XF501
49.95MHz
U102 NJM2902
IC101 TDA8547
TX/RX
SW
BPF
BPF
MIXER
CF501 450H
16.8MHz
TCXO
16.8MHz
To 50.4MHz
Q605
Q509
450_IF AMP
CODEC
Q506
3SK318
PLL
2SK72310
Loop
Filter RX VCO
U201
HR_C5000
U301
STM32F
300Hz
LPF
U101
CTCSS/DCS
Rx circuit mainly includes:
RF band-pass filter, low noise amplifier, frequency mixer, IF filter, IF amplifier, IF processor and audio
circuit.
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•Rx Circuit RF Part
The high frequency signal from low-pass filter passes the front stage electrically tunable band-pass filter
controlled by electric level and output by DAC (U301 PIN29) so as to filter out the out-of-band interference
signal, sending effective band-pass signal into the low noise amplifier (Q505). The amplified signal passes
again the band-pass filter controlled by electric level and output by DAC so as to filter out the out-of-band
interference signal caused by amplification, sending effective high frequency signal into frequency mixer
(Q506).
The effective signal passes RF band-pass filter and low noise amplification and enters the frequency
mixer Q506, meanwhile, the first local oscillation generated by VCO passes the low-pass filter and enters
Q506 for making frequency difference with effective signal so as to generate the first IF signal. The signal
passes the frequency selector network which consists of LC; it further suppresses the other carrier waves
other than the first IF, and increases the isolation between the frequency mixer and IF filter. The IF signal
will be filtered by the XF501 crystal filter, and then sent to the first IF amplifier (Q507) for amplification
before being sent to the IC for IF processing (U501, GT3136).
The third harmonic frequency 50.4MHz produced by TCXO(X601 16.8MHz) is amplified by frequency
selector and become the second local oscillation signal source. The second local oscillation (50.4MHz)
mixes with the first IF signal in U501, generating the second IF (450kHz). The second IF will be amplified,
limiting amplitude inside U501, and filtered by the ceramic filter CF501 450kHz before going back to U501
for demodulating and outputting the audio signal.
•Rx Circuit Audio Section
A. Digital Channel Audio Access: The second IF signal output from the eleventh pin of U501 is amplified
by Q509 and sent to U201 forADC sampling and being converted to digital signal; after the digital audio
signal is compressed, decompressed and decoded by U301, U201 will complete DA conversion and
output audio signal from the 10th pin, and the audio signal will be amplified by U203 and sent to the
audio power amplifier IC101.
B. Analog Channel Audio Access: The audio signal output from the 9th pin of U501 is amplified by U102
and its unit circuit. The high frequency and low frequency will be removed from the audio signal,
keeping only the voice component between 300 Hz to3000Hz. The voice component will be adjusted by
volume potentiometer and sent to audio power amplifier IC101.
C. Analog Channel CTCSS/DCS Signaling Access: The audio signal output from the 9th pin of U501
may include CTCSS/DCS signal. The 300Hz low-pass filter circuit composed of U101 filters out the
signals out of the CTCSS/DCS spectrum.After CTCSS/DCS is amplified, it will be sent to the 25th pin of
U301.
D. Analog Channel Squelch Circuit: The modulated output from U501 is sent to the frequency selector
noise amplifier which is composed of U501 internal noise amplifier and C555, R525, R524, C554, C553,
R527; the noise will be selected from the modulation signal and detected internally before being
outputting by the 14th pin and transformed as direct electric level to reach MCU U301; MCU identifies
the electric level strength and controls squelch.
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3.1.3.Frequency Synthesizer Circuit
Figure 3-4 Frequency Synthesizer Circuit Diagram
16.8MHz
TCXO
U601
2SK72310
LPF
X601
Loop
Filter
TX VCO
RX VCO
LD
CS
DATA
PS
MOD_Q
MOD_I
RF
Frequency synthesizer circuit is composed of VCO and PLL, and it is the kernel module of the whole TRx
system. When transmitting, the circuit supplies accurate carrier frequency; when receiving, it supplies
stable local oscillation signal. The circuit directly influences some of the important functions in the system.
•PLL Working Principle
The 16.8MHz frequency generated by the reference crystal oscillator enters the frequency divider of PLL
chip, and becomes reference frequency (i.e. step frequency f1). The frequency generated by VCO passes
LPF for filtering out the second harmonic wave and enters PLL chip for frequency division and gets
frequency f2. The frequency f2 compares with f1 on phase difference in phase comparator, producing
continuous pulse current. When the pulse current passes the loop filter, it starts to accumulate RC and
converts to CV voltage. The CV voltage is sent to the VCO varactor, directly controlling and adjusting the
VCO output frequency until CV becomes constant. PLL will be currently locked, and the stable frequency
output from VCO passes two buffer amplifiers before entering the TRx access.
•The Working Principle of Voltage Controlled Oscillator
The voltage controlled oscillator applies oscillation mode of three point capacitor. It changes the control
voltage of varactor to get different output frequency. Rx VCO is composed of oscillator circuit and Q603.
Tx VCO is composed of oscillator circuit and Q601, supplying carrier wave of TX signal.
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TP620 Service Manual
3.2.Power Section
Figure 3-5 Power Structure Diagram
Battery
SW401
POW_DET
POW_HOLD
RF PA
AF PA
U404
LDO
U403
LDO
U402
LDO
U401
DC-DC
5C
5R
5T
3.3V
Q401
Q402
U301
STM32F
SAVE
5RC
5TC
This radio applies 7.4V, 2000mAh lithium battery, RF power amplification (Q501, Q502), AF power
amplification (IC101), and direct battery power supply.
The power circuit is composed of power-on/off circuit, 5C, 5R, 5T, and 3.3V DC-DC voltage stabilizing
circuit.
Power-on Circuit: When SW401 is closed, the B level of Q402 becomes high electrical level, and the
switch tube Q401 becomes conductive. The power supplies electricity for every power module through
Q401, when MCU is powered on, POW_HOLD will output high electric level to keep Q401 constantly
conductive so as to turn on the radio.
Power-off Circuit: When SW401 is cut off, POW_DET test pin becomes low electric level, and
POW_HOLD pin of MCU will first stays on high electric level for a while before outputting low electric level.
The Q402 B level thus becomes low electric level, cutting off the switch tube Q401 and the power to turn
off the radio.
5C voltage stabilizing circuit: U404 applies 5V LDO voltage stabilizer and supply 5v power for PLL circuit.
Meanwhile, the 67th pin of U301 outputs high and low electric level to control the enable pin of U404,
making the voltage stabilizer switches between 5V and 0V so as to realize the functions such as energy
saving and Tx/Rx switch.
5R voltage stabilizing circuit: U403 applies 5V LDO voltage stabilizer, and supplies 5V power for Rx circuit.
Meanwhile, the 66th pin of U301 outputs high and low electric level to control the enable pin of U403,
making the voltage stabilizer switches between 5V and 0V so as to realize the functions such as energy
saving and Tx/Rx switch.
5T voltage stabilizing circuit: U402 applies 5V LDO voltage stabilizer, and supplies 5V power for Tx circuit.
Meanwhile, the 34th pin of U301 outputs high and low electric level to control the enable pin of U402,
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TP620 Service Manual
making the voltage stabilizer switches between 5V and 0V so as to realize the functions such as energy
saving and Tx/Rx switch.
voltage stabilizing circuit:U401 applies 3.3V DC-DC voltage stabilizer, and supplies 3.3V power for
U201,U301,U302,U307.
4.Function Description and Parameter Settings
4.1.Conventional Functions
•Supports private call, group call, all call on digital mode.
•Supports end-to-end voice encryption, data encryption.
•Supports short message.
•Supports Stun, Activate, and Digital Signaling Monitor in DMR standard.
•Supports CTCSS/CDCSS on analog mode
•Supports DTMF system on analog mode
•Supports emergency alarm feature
•Supports digital channel scanning, analog channel scanning.
•Supports a maximum of 32 channels
•Supports a maximum of two zones, and each zone contains16 channels.
•Supports a maximum of 1000 contacts.
•Supports LED, and alert tone which indicates option
•Supports programmable selection between 12.5 kHz and 25 kHz channel spacing.
•Battery power indication and low power alert feature.
4.2.Function Parameter Settings
The radios are set with default value when they are out of the factory. But due to the different requirements
by the users, the radio may be reset with operational frequency, channel parameter, scanning, encryption,
etc. Therefore, Kirisun specially designs a user programmable software which is interface-friendly,
operation-easily and display-visually to complete the parameter settings for the radio.
•Steps for parameter settings are as below:
Step 1. Confirm that the right version of TP620 user programmable software is installed on the computer.
Step 2. Confirm that the right version of TP620 USB driver software is installed on the computer.
Step 3. Use TP620 programmable lead supplied by Kirisun to connect the radio with computer USB port.
Step 4. Confirm that the radio is powered on.
Step 5. Operate TP620 user programming software.
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