BBK-AV225T-av-sm 电路图 维修手册.pdf

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1、 service manual AV225T RadioFans.CN 收音机爱 好者资料库 Catalog Chapter One About Maintenance 1.1 Safety precautions 1.1.1 Power supply 1.1.2 Precautions for antistatic 1.1.3 About placement position 1.2 Maintenance method 1.2.1 Visualized method 1.2.2 Electric resistance method 1.2.4 Current method 1.2.5 Cu

2、tting method 1.2.4Currentmethod 1.2.5Cuttingmethod 1.2.6 Element substitution method 1.2.7 Comparison method 1.3 Required device for maintenance Chapter Two Operation Instructions O i B T 2.1 Control button locations and explanations 2.1.1 Front panel illustratlons 2.1.2 Rear panel illustration 2.1.

3、3 llustrations to the 2.2 asic operations remote control 2.2.1 urn on/off this unit 2.2.2 tp function 2.2.3 Select Input Sound Source 2.2.4 Bass Enhancer 2.2.5 Select Sound Field 2.2.6 Adjust Volume 2.2.7 Adjust Level 2.2.8 EQ function 1 1 1 1 2 2 2 2 2 2 2 2 3 3 3 4 4 5 5 5 6 6 6 7 7 8 9 9 10 Radio

4、Fans.CN 收音机爱 好者资料库 Section One Principle of the Player 2.2.9 Parameter Processing 2.2.10 Adjust Karaoke 2.2.11 Tuning Function 2.2.12 Other Operations 3.1.4 The player signal flow chart Section Two Unit Circuit Principle 3.2.1 Volume board circuit 3.2.5 Power board circuit Section Three Servicing Ca

5、ses Section Four Servicing Parameters 3.4.1 Signal waveform diagram 3.4.2 Key point voltage Chapter Three Principle and Servicing 3.1.1 Composition of the player 3.1.2 Function and features 3.1.3 Player block diagram 3.2.2 Signal processing board circuit 3.2.3 MCU board circuit 3.2.4 Control panel c

6、ircuit 3.2.6 Power amplifier board and protection circuit 3.2.7 MIC, headphone board 3.2.8 Video in/out board circuit 3.3.1 Servicing instances 3.3.2 Troubleshooting process Section Five Function Introduction to IC 3.5.1 function introduction to 4558 3.5.2 function introduction to Pt2399 3.5.3 funct

7、ion introduction to Cd4051 3.5.4 function introduction to Cd4052 3.5.5 function introduction to Cd4053 3.5.6 function introduction to Sm79164 3.5.7 function introduction to Pt2308 3.5.8 function introduction to Pt2222 11 12 13 15 17 17 17 17 18 19 20 20 23 25 29 30 31 34 34 36 36 41 49 49 56 57 57 5

8、8 59 60 61 62 65 66 RadioFans.CN 收音机爱 好者资料库 V V S S C C A S V P R P S S 3.5.9 function introduction to Lm1875 3.5.10 function introduction to TDA7265 3.5.11 function introduction to M62446 3.5.12 function introduction to AT24C02 3.5.13 function introduction to L7805 3.5.14 function introduction to 7

9、812 3.5.15 function introduction to 7912 3.5.16 function introduction to LM324 3.5.17 function introduction to Pt2315 3.5.18 function introduction to 74VHC245 3.5.19 function introduction to Cd4094 Chapter Cinque PCB board when servicing, short- circuit and joint welding cannot occur, or else the el

10、ements will be burnt out and trouble range will be enlarged. Movement and friction will both bring static electricity which causes serious damages to integrated IC. Though static charge is little, when a limited quantity of electric charge is added to large- scaleintegrated IC, as the capacitance is

11、 very small in the meantime, now the integrated IC is very much easy to be struck through by static electricity or the performance will decrease. Thus static electricity prevention is of extraordinary importance. The following are several measures to prevent static electricity: 1. Use a piece of ele

12、ctric conduction metal with the length of about 2 metres to insert into the earth, and Fetch the lead wire from the top of the surplus metal and connect to the required static electricity device. The length and depth of the metal embedded under the earth should be determined according to the wettabi

13、lity of the local soil. For humid places, it may be shorter, and longer and deeper for dry places. If possible, it can be distributed and layed in terms of “ #”shape. 2. On operating table- board, the antistatic table cushion should be covered and grounded. 3. All devices and equipments should be pl

14、aced on the antistatic table cushion and grounded. 4. Maintenance personnel should wear antistatic wrist ring which should be grounded. 5. Places around the operating position should also be covered with electric conduction cushion or Painted with antistatic paint. -1 - 1.1.3 About placement positio

15、n 1.2.1 Visualized method 1.2.2 Electric resistance method 1.2.3 Voltage method 1.2.4 Current method 1.2.5 Cutting method 1. 2. Positions for placement should be stable and secure. Directly view whether abnormalities of collision, lack of element, joint welding, shedding welding, rosin joint, copper

16、 foil turning up, lead wire disconnection and elements burning up among pins of elements appear. Check power supply of the machine and then use hands to touch the casing of part of elements and check whether they are hot to judge the trouble spot. You should pay more attention when using this method

17、 to check in high voltage parts. Set the multimeter in resistance position and test whether the numerical value of resistance of each point in the circuit has difference from the normal value to judge the trouble spot. But in the circuit the tested numerical value of resistance is not accurate, and

18、the tested numerical value of integrated ICs pins can only be used for reference, so the elements should be broken down for test. Voltage method is relatively convenient, quick and accurate. Set the multimeter in voltage position and test power supply voltage of the player and voltage of a certain p

19、oint to judge the trouble spot according to the tested voltage variation. Set the multimeter in current position and test current of the player of a certain point to judge the trouble spot. But when testing in current method, the multimeter should be series connected in the circuit, which makes this

20、 method too trivial and troublesome, so it is less frequently used in reality. Cutting method should be combined with electric resistance method and voltage method to use. This method is mainly used in phenomena of short circuit and current leakage of the circuit. When cutting the input terminal vol

21、tage of a certain level, if voltage of the player rises again, it means that the trouble lies in this level. Audio power amplifier cannot be installed in places with high temperature and humidity. 1.2 Maintenance method -2 - 1.2.6 Element substitution method 1.2.7 Comparison method When some element

22、s cannot be judged good or bad, substitution method may de adopted directly. A same good PC board is usually used to test the correct voltage and waveform. Compared these data with those tested through fault PC board, the cause of troubles may be found. Through the above maintenance method, theoreti

23、cal knowledge and maintenance experience, all difficulties and troubles will be readily solved. Audio Generator Digital oscillograph (100MHE) SMD rework station Multimeter Soldering iron Pointed- month pincers Cutting nippers Forceps Electric screw driver Terminals connecting cord Headphone Micropho

24、ne 1.3 Required device for maintenance -3 - 2.1 CONTROL BUTTON LOCATIONS AND EXPLANATIONS 2.1.1 FRONT PANEL ILLUSTRATLONS Chapter Two Operation Instructions POWER SWITCH Power on/off this unit LCD Screen Buttons operation indication and spectrum display when working IR sensor Receive the infrared si

25、gnals transmitted from the remote control MASTER VOLUME- Press this button to synchronously lower all 6CH volumes INPUT Sound source input button MIC VOLUME+ Press this button to increase the volume of MIC MIC VOLUME- Press this button to lower the volume of MIC TUNING Select other frequency radio s

26、tations upwards 1 2 3 4 5 6 Tuning Select other frequency radio stations downwards BAND Select FM/AM tuner BAND PRESET Select the latter preset radio station PRESET Select the previous preset radio station MODE Select tuner mode:manual/auto MASTER VOLUME+ Press this button to synchronously increase

27、all 6CH volumes STANDBY Standby COVER OF PHONE JACK AND MICROPHONE JACK 9 10 11 12 13 14 15 167 8 - 4 - AC-3/DTS 5.1CH INPUT 5.1CH audio signals input terminals that connect to DVD, AC-3/DTS AM/FM antenna terminal Connect AM/FM antenna outside Stereo Audio jack The terminals that connect with VCD, D

28、VD stereo audio signals input Video input The terminals that connect with VCD,DVD Video signals input Video output jack The terminals that connect with TV Video signal output 1 2 3 4 5 Data The data plate of this unit SERIAL NO. Mark The manufacturing records CAUTION mark Remind the user of dangerou

29、s voltage inside Line-out Subwoofer signals line-out jack This units manufacturer Terminals Connect with SPEAKER terminals 6 7 8 9 10 11 2.1.2 REAR PANEL ILLUSTRATION 2.1.3 ILLUSTRATIONS TO THE REMOTE CONTROL STANDBY button: Power on, STANDBY switch button DISPLAY button: Select audio spectrum displ

30、ay modes MUTE button: Mute On/Off button INPUT button: Select input signal sources manually MOVIE button: OTP button to set standard movie theater surround mode MUSIC button: OTP button to set standard concert mode K.R.OK: OTP button to set standard Karaoke mode HI- FI button: Select the Hi- Fi soun

31、d field STANDARD button: Select the standard sound field CYBER LOGIC button: Select the cyber logic sound field BASS ENHANCER button: Select the bass enhancing effect 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Number buttons 18: Select 8 preset working modes with the help of SAVE/CALL button, capable of stori

32、ng and calling the user-set working mode parameters SPEAKERS button: Adjust the separate channel level with the help of / keys CHILD LOCK button: Lock the functions of the front panel controls SURR. Button: Select the surround sound field DEFAULT button: Restore the factory default settings SAVE but

33、ton: Store the current working mode parameters with the help of number buttons 18 CALL button: Call the user-stored working mode parameters with the help of number buttons 18 EQ select button: Select the equalization frequency MULTI-BAND EQ button:Adjust multi-band electronic equalization Adjust but

34、ton: Adjust level and multi-band EQ EQ button: Circularly call the preset EQ modes AUTO EQ button: Analyze the current signal spectrum, automatically set EQ parameters 15 16 17 18 19 20 21 22 23 - 5 - 29 30 24 25 26 27 28 VOLUME button: Adjust the karaoke level with /keys ECHO button: Adjust the kar

35、aoke ECHO with /keys VOICE MODIFY: MODIFY button: Select Karaoke voice modify WF button: Karaoke wide sound field On/Off TONE button: Adjust the karaoke BASS/Treble tone levelwith /keys DELAY button: Adjust the karaoke delay time with / keys MASTER VOL button: Synchronously increase/decrease 6 chann

36、els volume BAND button: Select FM/AM tuner band MODE button: Select tuner mode:manual/auto STEP button: Select AM tuning step:9K/10K MEMORY button: Memory the received radio station with the help of number buttons 09 CLEAR button: Clear the preset radio station with the help of number buttons 09 TUN

37、ING : Scan other frequency radio station upwards TUNING : Scan other frequency radio station downwards PRESET : Select the latter preset radio station PRESET : Select the previous preset radio station NUMBER 09 :Save the received radio station programs or directly call the preset programs with the h

38、elp of MEMORY button 31 32 33 34 35 36 37 38 39 2.2 BASIC OPERATIONS 2.2.1 TURN ON/OFF THIS UNIT Please check the connection cords before turning this unit on. If all connections are correct, you can connect this unit to power. Press the POWER button, this unit enters the standby mode . When this un

39、it is in the standby mode, it detects the input signals automatically. When there is signal input, this unit turns on automatically. When the input signal is too small, this unit might not detect the signal and will not turn on automatically. When there is signal input and the unit cannot turn on au

40、tomatically, press the STANDBY button on the front panel or remote control to operate manually and select input signals by using the INPUT button. When the unit is in the standby mode, press the STANDBY button on the front panel or remote control to turn on this unit. Press the STANDBY button on the

41、 front panel or remote control. After turning on this unit, it detects the input signal automatically. When there is signal input, it receives the input signal automatically. Otherwise, the unit will automatically search signals all the time. When there is signal input but it cannot receive The sign

42、al automatically, press the INPUT button on the remote control to select the input signal. When the unit is in normal working mode, press the STANDBY button on the front panel or remote control if you want to enter standby mode. Please turn off the power when you are not going to use the unit for a

43、long time. Please turn off the power every time after you use the unit. Press the POWER button on the front panel to power off this unit. POWER 2.2.2 OTP function We have set the OTP function to simplify the operation of testing sound effects.If the played disc is movie or story, you just press the

44、MOVIE button and the system will automatically set standard movie mode.If the played disc is music, you just press the MUSIC button and the system will automatically set standard music mode.If you want to sing Karaoke, you just press the - 6 - K.R.OK button after inserting microphone and The system

45、will automatically set standard Karaoke mode. Press the MOVIE button to set standard theater surround mode. Automatically detect the input signal source. If many signal sources input, it will select the current signal input preferentially. Automatically set the parameters of surround. If 5.1CH input

46、 signal is detected, it will automatically adopt standard mode; if 2CH signal source is detected, it will automatically adopt Cyber Logic. Press the MUSIC button to set standard music modeAutomatically detect the input signalsource. If many signal sources input, it will select the current signal pre

47、ferentially. Automatically set the parameters when enjoying music. If 5.1CH input signal is detected, it will automatically adopt standard mode;if 2CH signal source is detected, it will automatically adopt Hi-Fi mode. Press the K.R.OK button to set standard Karaoke mode. Automatically detect the inp

48、ut signal source. If many signal sources input, it will select the current signal preferentially. Automatically set the parameters of Karaoke mode. NOTE: If the signal is too weak or in the blank segment of music when operating, the system will probably appear wrong indications. 2.2.3 Select Input S

49、ound Source This unit utilizes two input lines of stereo audio sources: VCD, DVD; one line 5.1 channel signal input. Select the input signal source manually through the remote control. Press the INPUT button on the remote control, and INPUT TUNER splays, which means TUNER has been selected. Press the INPUT button on the remote control, and INPUT VCD displays, which means VCD 2CH input jack has been selected. Press the INPUT button on the remote control, and INPUT DVD