PX-777维修手册
UHF/VHF FM TRANSCEIVER
PX-777/328/338 SERVICE MANUAL
------------------CONTENTS-------------------------- INTRODUCTION (2)
GENERAL (2)
REALIGNMENT (3)
TROUBLE SHOOTING GUIDE (6)
TECHNICAL SPECIFICATION ............................................. (7)
FUNCTION SPECIFICATION (8)
CIRCUIT DESCRIPTION (9)
SEMICONDUCTOR DATA (16)
PARTS LIST (17)
BLOCK DIAGRAM (22)
PCB BOARD (23)
SCHEMATIC DIAGRAM (25)
INTRODUCTION
SCOPE OF THIS MANUAL
This manual is intended for use by experienced technicians
familiar with similar types of commercial grade communications
equipment. It contains all required service information for the
equipment and is current as of the publication 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 information,
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 required
component for proper identification.
PERSONNEL SAFETY
The following precautions are recommended for personnel
safety:
DO NOT transmit until all RF connectors are verified secure
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 technician only.
SERVICE
This radio is designed for easy servicing. Refer to the
schematic diagrams, printed circuit board views, and alignment
procedures contained within.
GENERAL
Your Transceiver is an electronic product of exact design and should be treated with care .The suggestions below will help you to fulfill any warranty obligations and to enjoy this product for many years.
Do not attempt to open the unit. Non-expert handling of the unit may damage it.
When using regulated power supply, take notice of power voltage must be between 6V and 8V to avoid damaging the unit.
Do not store the Radio under the sunshine or in hot areas.
High temperatures can shorten the life of electronic devices, and warp or melt certain plastics.
Do not store the Radio in dusty, dirty areas
Keep the Radio dry. Rainwater or damp will corrode electronic circuits.
If it appears that the Radio diffuses peculiar smell or smoke, please shut off its power immediately and take off charger or battery in the Radio, then contact with PUXING agency.
Do not transmit without antenna.
REALIGNMENT
1. MODE:
USER MODE: For normal use, when turn on enter this mode.
PC MODE: used to read and program radio.
SELF-PROGRAMMING MODE: Hold down [MONI] and [menu] key accomplished by turning on the VOL/POWER switch until “SELF” displays.
2.
2. LCD DISPLAY
3. SELF-PROGRAMMING MODE
For frequency,signal,feature write to the radio
TECHNICAL SPECIFICATION
General
Frequency Range 136―174MHz，350—390MHz，400—
470MHz,245Mhz
Working Temperate －20℃―＋50℃
Operating V oltage DC 7.2V
Operate Mode Simplex or Semi-duplex
Channel spacing 25Khz/12.5Khz
Dimension 100mm×55mm×32mm (Not included Antenna) Weight 220g (Including battery)
Antenna impedance 50Ω
Transmitter
Frequency Stability ±2.5PPM
Output Power 5W/4W ±0.5W
Max Frequency Deviation ≦5KHz
Audio Distortion ≦3%
Modulation Character +3dB—-3dB
Adjacent Channel Power ≥65dB
Spurious Radiation ≤7.5UW
Occupied Bandwidth ≤16KHz
Receiver
RF Sensitivity ＜0.2UV
Audio Distortion ≦3%
Audio Response +2dB—-10dB
Adjacent Channel Selectivity ≥60dB
Intermodulation Rejection ≥60dB
Spurious Response ≥60dB
Blocking ≥80dB
CPU PIN FUNCTION PX-777 ITEM DESCRIPTION I/O FUNCTION 1CLK ROM I/O CLOCK AND EEPROM
2D0O Key scan output
3D1O Key scan output
4D2O PLL clock port/Key scan output
5D3O PLL data port/Key scan output
6PLL CS O PLL CS port
7LAMP2O Lcd/backlight control output
8K1I Key scan input
9K2I Key scan input
10K3I Key scan input
11K4I Key scan input
12AVDD MPU+5MV
13RX0O IF output control port
14RX1I IF input control port
15TX1I MIC input control port
16TX0O MIC output control port
17BEEP/QT O BEEP output /CCTCS tone signal output
18ACC MPU power filter
19AVSS Connect to VSS
20APC/TUNE O Automatic power &frequency automatic gain output 21AT X O Transmitter data output select control
22AR X I Receiver data input/audio amplifier adjustment input 23BATT Test O Battery check /Reset
24VOX I VOX input
25AN SQL I Squelch signal input port
26OSCin I Internal oscillator input
27OSCout O Internal oscillator output
28VSS GND
29EN1I Encoder data input
30EN2I Encoder data input
31MONI I Monitor key input
32Reset I CPU reset port
33Vdd+5V power supply
345TC O TX power supply control output
35LED G O LED green
36TXD/LED R O RX232 output/ LED red
37AFC O Audio amplifier control input
385CC O Power supply control output
39P-AMP O Audio amplifier power supply control output
40N/W/LD O Unlock detection
41PTT/RX D I PTT key input/RX232 input
42HT1621 CS I LCD CS port
43LAMP1O Backlight control output
Footprint
Comment Quantity 电容类
备注C0402
0.5P 2C332C349C0402
1P 1C231C0402
1.5P 1C346C423
C456C315C317_2C313_2C175C535
C536C537C538C315_2C314_2C416
C415CAP CAP C593CAP C387_1
C318_1C316_2C312_2C326_1C227C121
C132C135C133C142C144C156
C223C222C322C612CAP R808
C386_1C146C145C176C122C123
C455C515C413
C269C254C610C451C623
CAP C633C529C528C613C450
C665_1C105C581C520C701C174
C181C244C247C321C351C668
C454C621CAP C594C301C514
C392C391CAP
CAP C257C268C266C267C411
C453C202C203C561C271C663_1
C388_1C319_1C250CAP C103
C101C573C571C511C521C182
C208C316CAP C354C662CAP
C302C418C102C147C661C201
C131C0402105P 4C517
C611C609C664C263
C255C361C363C362C213C348
C330C331C0402120P 1C259
C040212P 3C224
C241C359C040215P 1C113
C040218P 318NH
C523C246C04021P 2C327
C329C264
C265C394C513C512C592C591
C0402222P 1C272
C0402223P 2C421
C417C0402224P 1C256
C040222P 1C353
C0402273P 3C414
C556C555
C040227P 1C134
C0402332P 2C426
C432C0402333P 1C516C0402220P 732103P C040237104P C0402PX777 part list(136-174MHz)
33102P C0402C0402100P 12Designators 910P C0402
C0402
33P 2C126C343C04023P 2
C226C232C262C258C546C666C311C221C112C111C127C125C141C233C177C317C243C314C355C312C356C358C313C204CAP C310C412C622C632C531C534C533C180C260C532C173C667C0402
473P 3C424C431C458C0402
47P 2C393C324C0402
5P 2C215C347C0402
680P 2C428C433C0402
683P 1C543C0402
6P 1C352C0402
82P 1C395C0402
8P 3C211C229C2350603电容
C0603
10P 5C163C167C165C169C154C0603
15P 3C153C161C164C0603
20P 1C152C0603
22P 3C168C166R818C0603
470P 1C162C0603
56P 1C155C0603
6P 2C325C344C0603
104P 1L333太阳电诱
C0805
0.1uF 4E367_1E364E411C541C0805
1uF 4E454E319_1C104C143C0805
2.2uF 4E435E413E363_1E474E412E242E326_1E180E311E273R0402电阻
L121R457R663R364_1R363_2R235R134R362C251R662R0402
1.8K 1R365_1R413R301R524R113R131R363R321R314R352R594R595R269R547R529R528R391R351R459R809R223R258R429R434R453R201R543R184R333R203R111R561R101R361_2R820R0402
10R 4R458R127R125R354R541R582R392R172R175R174
R173R170R171R583R0402
150R 2R456R362_2R040215K 4R519R52215K R478C0805
4.7uF 6R0402
0R 10111410K R0402
100R 150K C0402470P 35
9100K R0402
R0402
R0402
10
R0402
180K 2R265R263R0402
18K 2R414R187R573R591R593R251R254R411R666R312_2R313R667R668R417R596R393R0402
1K52R421R124R0402
1M 2R664_1R183R0402
1M82R428R433R0402
2.2K 1R261R0402
2.7K 1R259R0402
220K 4R252R551R181R512R0402
220R 6R389_1R331R348R312R571R244R0402
20K 3R544R472R436R0402
22K 4R552R415R313_2R515R0402
22R 2R112R315R0402
270k 1R665R0402
270R 3R156R155R358R0402
27K 3R556R141R555R255R452R451R455R202R302R103R516R0402
3.3K 3R367_1R366_1R264R0402
30K 2R422R177R0402
330R 3R128R811R126R426R427R431R432R42333K R0402
39K 1R554R0402
3K34R435R355R359R357R0402
3K91R123R0402
470R 1R572R0402
470K 1R553R518R592R525R527R526R322R581R132R142R186R182R597R222R221R387R0402
47R 4R326_1R133R143R247R272R273R574R575R576R243R311R538R262R271L342L323R0402
560R 3R412R368_1R110R0402
56K 2R311_2R517R0402
5K62R661R356R0402
680K 1R416R0402
680R 1R114R0402
68K 2R542R185R0402
6K81R424R0402
82K 2R521R523R0603
0R 3L591L133L331
R1206电阻4K71282K2R0402
1K R0402
R0402
R0402
633K R0402
141547K
R1206
0.393R104R105R106L0603电感
L411L511L111L122100NH C697高频叠层L326_1L313L315L0603
101T 1L521瓷珠L0603
1UH 1L391L0603
220NH 5R807L354L351L348L242高频叠层L0603
33NH 1L143高频叠层L0603
47nH 1L352高频叠层L0603
560UH 1L392L0603
6.8UH 2L321L341L611L640L131L141L227瓷珠瓷珠L1008R124
L325L343L248L316绕线L0805R221
L155丰华绕线L13101uH 1
L168太诱绕线L25201R02
L246L132太诱绕线L080568NH 3
L225L229L241高频叠层L0805R151
L215绕线二极管类D_ESC B94
D322D321D342D341D_ESC HSC2774
D212D235D211D111D_SMA 1SR154-4001
D611D_USC 1SV2201
D323D_USC MA771
D155D0603GREEN 1
D571D0603RED 1
D573D-ESC PMSD41482
D312_1D311D-USC 3V 1
R806D-USM-MA742MA7421
D661_1集成类SOP824C161
U561SOP8LM45581
U411SOT243SK2412
T241T221SOT892SC49881
T121SRP810K 1
PR511SRP81K 2
PR752PR311 1SSOP10-P-225TA7368F 1
U451SSOP16-225TA311361
U261SSOP8LM2904V 1
U170U-SSOP20-225LMX23321
U311_1三极管类T_ESM 2SC46173
T311T421T431T_ESM 2SJ2431
T312T_ESM 2SK18241
T541T_ESM DTA114EE 2
T261T573T_ESM DTC114EE 3T451T571T572
L08059100NH 5
101T L0603