Kirisun PT6808-02 User manual

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Dangerous!
Do not connect AC power or DC power over 13.8V to any connector or terminal of the radio.
Otherwise it will cause fire, electric shock or damage to the radio.
Warning!
Do not reverse power polarity.
It may cause harm to the radio if signal input on the antenna connector is higher than 20 dBm
(100mW).
Do not turn on the radio until the antenna or load connection is completed.
If the antenna has been damaged, do not use the radio. Damaged antenna may cause light burning
on skin.
Though the radio is waterproof, it's better to avoid putting it in rain or snow, or any other liquid
to ensure its life and performance.
Statement!
Kirisun Communications Co., Ltd owns the copyright of KSP6808 software.
Duplication of KSP6808 software is allowed.
Kirisun Communications Co., Ltd owns the copyright of the MCU software code.
Kirisun Communications Co., Ltd owns the copyright of the radio outward
appearance/structure/circuit design.
Kirisun Communications Co., Ltd owns the copyright of this service manual. Unauthorized
publication is prohibited.
Kirisun Communications Co., Ltd owns the trademarks “KIRISUN”, “ ”, “ ”, and
“科立讯”.
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Contents
Chapter 1 Overview ........................................................................................................................3
Chapter 2 External View and Functional Keys...............................................................................4
Chapter 3 Mode Introduction..........................................................................................................7
Chapter 4 Circuit Description .........................................................................................................7
Chapter 5 Function Description and Parameter Settings ..............................................................14
Chapter 6 Disassembly for Repair ................................................................................................17
Chapter 7 Adjustment ...................................................................................................................22
Chapter 8 Specifications ...............................................................................................................29
Chapter 9 Servicing and Testing Equipment.................................................................................30
Chapter 10 Troubleshooting..........................................................................................................31
Appendix 1: Abbreviations ...........................................................................................................33
Appendix 2 Semiconductor Data..................................................................................................34
Appendix 3 Electronic Components .............................................................................................38
Figure 1 PT6808 Block Diagram..................................................................................................58
Figure 2 PT6808 RF Board Position Mark Diagram....................................................................59
Figure 3 PT6808 RF Board Position Mark Diagram....................................................................60
Figure 4 PT6808 Key Board Position Mark Diagram ..................................................................61
Figure 5 PT6808 Key Board Position Mark Diagram ..................................................................62

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Chapter 1 Overview
1.1 Introduction
This manual applies to the service and maintenance of PT6808-02 and PT6808-03 trunking
portable radios, and is intended for use by engineers and professional technicians that have been
trained by Kirisun. It contains all required service information for the equipment. Kirisun reserves
the right to modify the product structure and specifications without notice in order to enhance
product performance and quality. You can also contact your local dealer or us to get the latest service
manual.
Please read this manual before repairing the product.
1.2 Safety Precautions
* Electromagnetic Energy Radiation
Radios will generate and radiate electromagnetic energy during transmit mode.
The safety design of Kirisun radios complies with national and international standards.
In order to obtain best performance, and to guarantee that the electromagnetic radiation does no
harm to you, always keep the radio vertical to the ground and make sure that the microphone is
2-5cm from your mouth while using the radio.
* Electromagnetic Interference
In order to avoid electromagnetic interference, please turn off the radio in the place where such post
prompts you to do so, e.g. hospital, health care center, airport, etc.
* ExplosiveAtmosphere
It’s prohibited to use or repair the radio in the following places:
Hospital, health center, airport, or where “TURN OFF TWO-WAY RADIO” signs have been
posted.
Any area with a potentially explosive atmosphere (e.g. orlop deck of the ship, storage and
transportation equipment for fuel and chemical etc.)
Any place near blasting sites or area with electrical blasting cap.
It is also prohibited to change or charge the battery in any area with a potentially explosive
atmosphere.
* Antenna

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If the antenna has been damaged, do not use the radio. Damaged antenna may cause light burning
on skin.
* Replacement Parts
All components used for repair should be supplied by Kirisun.
Components of the same type available on the market are not surely able to be used in this
product and we do not guarantee the quality of the product using such components.
If you want to apply for any component from Kirisun, please fill in an application form as below.
e.g.
Component Application Form
Radio Model Component Position
Mark
Model/
Specifications Parts No. Qty
PT6808-02 FET Q3 RD01MUS1 105-RD01MU-R01 1
PT6808-03 Triode Q49 2SC5108（Y）104-SC5108-001 1
1.3 Service
All the Kirisun products are subject to the service warranty.
The warranty of the host is 18 months. The warranty of the accessories, including battery, charger,
earphone, antenna and adapter, is 6 months. However, in one of the following cases, charge free
service will not be available.
* No valid warranty card or original invoice.
* Malfunction caused by disassembling, repairing or reconstructing the radio by users without
permission.
* Wear and tear or any man-made damage such as mechanical damage, burning or water leaking.
* Product’s serial number has been damaged or the product trademark is difficult to identify.
After the warranty expires, lifetime service is still available. We also provide service components
to service stations and staffs.
Chapter 2 External View and Functional Keys
2.1 External View and Functional Keys

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Figure 1
Figure 2
2.2 Key operation descriptions
A. Power Button
B. LED indicator
C. Emergency alarm Button (trunking mode)
D. Clear Button (trunking mode)
E. MONI Button (Normal mode), wide/narrow band switch (test mode)
F. Volume Knob
G. Redial Button (trunking mode)
H. PTT Button
I. Encoder Button (clockwise)

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J. Encoder Button (counterclockwise)
K. Connector for hand microphone, programming line
O. Numeric keypad: press the key to input the number you want to call.
P. Programmable Keys: Key A, B, C and D. They can be programmed to execute the following
functions by PC software: None, Clear, Redial, Menu, Status Info., Emergency, UP and DOWN.
Q. PTT Key of hand MIC: press down to make or send a call.
2.3 Connectors on the rear panel
L．Connector for power supply
M．SL16J antenna connector
N．Connector for speaker/MIC
2.4 Display screen
Icon Description
Indicates the signal strength.
SVC Indicates that the radio is hunting for a control channel.
MON Indicates that you are monitoring a channel.
SCN Appears while you are scanning
Lo Indicates that the radio is transmitting in low power.
Appears when you are in home system, and disappears when
in roaming.
Appears when there is new data received, including voice
message, digital data message and missed calls.

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Appears when you are in roaming.
Appears when the keypad is locked.
Appears when the ring alert function is active.
Indicates the current battery power level.
Chapter 3 Mode Introduction
3.1 Mode Introduction
Mode Function How to Enter
User
Mode
Trunking Mode
For normal user.
Default step: Press the programmed DOWN key
(Hand MIC) to enter Conventional Mode while in
Trunking Mode.
Conventional
Mode
Combination step: press the programmed
combination keys set in PC software to switch
between the two modes.
Panel Test Mode
Used by the dealer to
check the
fundamental
characteristics.
Press and hold the programmed Status Info. Key
(Hand MIC) while turning the radio power ON.
Panel Tuning Mode Used by the dealer to
tune the radio.
Press and hold the programmed Menu key (Hand
MIC) while turning the radio power ON.
Version Information Mode Used to check the
version.
Press and hold the programmed DOWN key while
turning the radio power ON.
3.2 Panel Test Mode
Please refer to Chapter 7 Adjustment.
3.3 Panel Tuning Mode
Please refer to Chapter 7 Adjustment.
Chapter 4 Circuit Description
4.1 Preface
This mobile radio is FM trunking mobile equipment which works among 350MHz-390MHz.

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4.2 Frequency Configuration
Figure 1: Frequency Configuration
The receiver adopts superheterodyne double frequency conversion of the first IF of 44.85MHz
and the second IF of 455kHz.
The first IF of 44.85MHz is generated by mixing the signal received from the antenna with the
local oscillator signal coming from the phase lock loop.
Then the output signal is mixed with the second local oscillator signal of 44.395MHz to generate
the second IF of 455kHz. And then this frequency is checked and generates demodulating signal.
PLL voltage controlled oscillator generates the Rx signal frequency, and is modulated by the
signal from the microphone. Then the signal is amplified and sent to the antenna.
4.3 Principle of Receiver (RX)
Figure 2 Principle of Receiver
4.3.1 RF circuit

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The RF signal received by the antenna comes to antenna switch (D28, D29 and D26), and passes
through a BPF (L27, 36, 37, 38 and 39) which is adjusted by variable capacitance. The voltage
output from the variable capacitance passes through the voltage from the digital/analog conversion
and is modulated. The signal is amplified by RF amplifier Q35, and passes through BPF (L32, 33, 34,
35) and frequency band clear filter (L15.17) to continue to filter the unwanted signal. Then the
output signal comes to the first mixed tube (Q34), and mixes with the first local oscillator signal of
the frequency synthesizer to generate the first IF (44.85MHz).
4.3.2 IF circuit
The first IF signal passes through crystal filter (XF1 and XF2) to filter the signal coming from
the adjacent channel. The output signal is amplified by the first IF amplifier (Q12), and then comes
into IF system chip (IC12). IF system chip servers as the second mixer, the second local oscillator,
amplitude limit amplifier, quadrature detector and RSSI (receiving signal strength indicator). The
second mixer mixes the first IF signal with the second local oscillator signal (crystal part X2) of
44.395MHz, and then generates the second IF of 455 kHz.
The second IF signal passes through ceramic filter (CF: wide; CF: narrow) to continue to filter
the unwanted signal from the adjacent channel. The output signal is amplified by the voltage limit
amplifier and is demodulated by the quadrature detector with ceramic filter (CD1). The demodulated
signal then comes to audio circuit.
4.3.3 Wide/narrow band switch circuit
To set the wide/narrow band of each channel, turn on the ceramic filter CF1 (wide), CF2
(narrow).
The 99 pin of IC19 (micro-computer) outputs the wide band (high power level) and narrow (low
power level) signal.
If the circuit receives the wide band (high power level) data, Q6 disconnects and Q7 connects; if
the circuit receives the narrow band (low power level) data, Q6 connects and Q7 disconnects; if the
circuit receives high/low power level data, D5 and D7 turns on the ceramic filter.
Q9 is connected/disconnected as wide/narrow data receives. The output power level of IC12
detector varies to ensure that the output power level during the wide/narrow band switch is
invariable.
4.3.4 Audio amplifier circuit
The demodulated signal coming from IC12 passes through mute switch (Q15), and then is