KX-TG5771BXS/KX-TGA570BXS 1 Safety Precautions 1.1. For Service Technicians ICs and LSIs are vulnerable to static electricity. When repairing, the following precautions will help prevent recurring malfunctions. 1. Cover plastic parts boxes with aluminum foil. 2. Ground the soldering irons. 3. Use a conductive mat on worktable.
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KX-TG5771BXS/KX-TGA570BXS 2.2.1. Suggested PbF Solder There are several types of PbF solder available commercially. While this product is manufactured using Tin, Silver, and Copper (Sn+Ag+Cu), you can also use Tin and Copper (Sn+Cu), or Tin, Zinc, and Bismuth (Sn+Zn+Bi). Please check the manufac- turer’s specific instructions for the melting points of their products and any precautions for using their product with other materi-...
KX-TG5771BXS/KX-TGA570BXS 4 Technical Descriptions 4.1. FHSS Description 4.1.1. Frequency The frequency range of 5.76 GHz-5.84 GHz is used. Transmitting and receiving channel between Base Unit and Handset is same frequency. Refer to Frequency Table (P.83). 4.1.2. FHSS (Frequency Hopping Spread Spectrum) This telephone is using an IC chip which has similar specification to WDCT (World Digital Cordless Telephone) and is the tele- phone system that can use multiple portable unit simultaneously.
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KX-TG5771BXS/KX-TGA570BXS 4.1.2.1. TDD Frame Format Sync Field (72 bit): Preamble 56 bit + SyncWord 16 bit Base Unit (Handset) adjusts the timing of reception so that reception of Base Unit (Handset) can correspond to transmission of Handset (Base Unit). It is necessary for sync-field that Handset gets synchronization.
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KX-TG5771BXS/KX-TGA570BXS 4.1.3. Signal Flowchart in the Whole System Reception CN101 of the Base Unit is connected to the TEL line, and signal is enter through the bridge diode D101. While talking, the relay (Q141) is turned ON and amplified at the Q171, then led to DSP (IC501). The DSP encodes ADPCM and TDD/TDMA with FHSS to TXMOD.
KX-TG5771BXS/KX-TGA570BXS 4.5. Circuit Operation (Base Unit) General Description: (DSP, Flash Memory) is a digital speech/signal processing system that implements all the functions of speech compression, record and playback, and memory management required in a digital telephone answering machine. The DSP system is fully controlled by a host processor DSP. The host processor provides activation and control of all that functions as follows.
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KX-TG5771BXS/KX-TGA570BXS 4.5.3. Power Supply Circuit Function: The power supply voltage from AC adaptor is converted to the desired voltage of each block. Circuit Operation: • Q300 and IC300: 4.0 V DCDC Converter • IC331: 3.3 V Regulator...
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KX-TG5771BXS/KX-TGA570BXS 4.5.3.1. Charge Circuit The voltage from the AC adaptor is supplied to the charge circuits. Main charge (130 ~ 220 mA at the Battery) of maximum 7-hours is started soon after the Handset is placed on the Base Unit. Then it changes to Trickle charge to prevent from overcharging.
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KX-TG5771BXS/KX-TGA570BXS 4.5.4. Reset Circuit Function: This circuit is used to initialize the microcomputer when it incorporates an AC adaptor. Circuit Operation: When the AC Adaptor is inserted into the unit, then the voltage is shifted by IC331 and power is supplied to the DSP.
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KX-TG5771BXS/KX-TGA570BXS 4.5.5. Telephone Line Interface Telephone Line Interface Circuit: Function • Bell signal detection • ON/OFF hook and pulse dial circuit • Side tone circuit Bell signal detection and OFF HOOK circuit: In the idle mode, Q141 is open to cut the DC loop current and decrease the ring load. When ring voltage appears at the Tip (T) and Ring (R) leads (When the telephone rings), the AC ring voltage is transferred as follows: T →...
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KX-TG5771BXS/KX-TGA570BXS 4.5.6. Auto Disconnect circuit Function: This circuit is used to detect the fact that another telephone connected to the same line is OFF-HOOK while the unit is in a receiving status or OGM transmitting status. Circuit Operation: The voltage of pin 90 of IC501 is monitored. If a parallel-connected telephone is put into OFF-HOOK status, the presence/ absence of a parallel connection is determined when the voltage changes by 0.2 V or more.
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KX-TG5771BXS/KX-TGA570BXS 4.5.7. Parallel Connection Detect Circuit Function: In order to disable call waiting and stutter tone functions when using telephones connected in parallel, it is necessary to have a circuit that judges whether a telephone connected in parallel is in use or not. This circuit determines whether the telephone connected in parallel is on hook or off hook by detecting changes in the T/R voltage.
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KX-TG5771BXS/KX-TGA570BXS 4.5.8. Calling Line Identification (Caller ID) Function: The caller ID is a chargeable ID which the user of a telephone circuit obtains by entering a contract with the telephone company to utilize a caller ID service. For this reason, the operation of this circuit assumes that a caller ID service contract has been entered for the circuit being used.
KX-TG5771BXS/KX-TGA570BXS 4.8. Circuit Operation (Handset) 4.8.1. Construction The circuit mainly consists of DSP and RF part as shown in the block diagram. 4.8.1.1. DSP: IC201 Function • Battery Low, Power down detect circuit • Ringer Generation • Interface circuit RF part, Speaker, Mic, LED, Key scan, LCD, Headset...
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KX-TG5771BXS/KX-TGA570BXS 4.8.2. Power Supply Circuit Voltage is supplied separately to each block.
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KX-TG5771BXS/KX-TGA570BXS 4.8.3. Charge Circuit When the Handset is put on the cradle of the Base Unit or the charger, the power is supplied from CHARGE+ and CHARGE- terminals to charge the battery via Q361 or R366, and D361. The voltage between CHARGE+ and CHARGE- flows R231 →...
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KX-TG5771BXS/KX-TGA570BXS 4.8.5. Sending Signal The voice signal from the microphone is input to DSP (89, 90). CN331 is the headset jack. When the headphone is connected, the Q331 detect it. The input from the microphone of the Handset (MIN, MIP) is cut and the microphone signal from the headset is input to DSP (94).
KX-TG5771BXS/KX-TGA570BXS 4.9. Circuit Operation (RF Part) General Description: RF part includes Transmitter and Receiver functions. Digital signals (Mainly voice data) that come from DSP, are modulated and are transmitted. On the other hand, received signals are demodulated and go out to DSP.
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KX-TG5771BXS/KX-TGA570BXS 4.9.1. Power Supply Circuit As indicated below, the various voltages are supplied to each block. V_PA, about 4.0 V at Base Unit or 3.1 V at Handset, is supplied to the Power amplifier in 5.8 GHz PA circuit. IC841 is 3.0 V (Base Unit) or 2.8 V (Handset) Regulators, and IC761 is a 2.5 V Regulator. They output Vcc_5.8 GHz, and Vcc_2.4...
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KX-TG5771BXS/KX-TGA570BXS 4.9.2. 2.4 GHz Mod/Demod Circuit IC701 incorporates all of the modulation and demodulation functions. TX Digital data (TX_DATA) from DSP is supplied to pin 27 of IC701, and then 2.4 GHz TX modulated signal is output from pin 1. This TX signal goes into the 5.8 GHz Converter circuit. 2.4 GHz RX signal from 5.8 GHz Converter circuit is passed through matching circuit and supplied to pin 4 of IC701, then demodulated...
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KX-TG5771BXS/KX-TGA570BXS 4.9.3. 5.8 GHz Converter Circuit This block converts frequency of TX signal and RX signal. IC801 includes TX-MIXER, RX-MIXER, PLL and VCO modules internally. The VCO module is tuned by PLL synthesizer module, and generates 3.4 GHz Local signal. Reference clock (13.824 MHz) from DSP block is supplied to pin 7 of IC701.
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KX-TG5771BXS/KX-TGA570BXS 4.9.4. 5.8 GHz PA (Power Amplifier), 5.8 GHz LNA (Low Noise Amplifier) and Antenna Switch Circuit PA block amplifies power of 5.8 GHz TX signal. 5.8 GHz TX signal from 5.8 GHz Converter circuit is filtered by 5.8 GHz-BPF FL811, and amplified by Power amplifier (PA) block of IC851.
KX-TG5771BXS/KX-TGA570BXS 4.10. Circuit Operation (Charger Unit) The voltage from the AC adaptor is supplied to the charge circuits. Main charge (130 ~ 220 mA at the Battery) of maximum 7- hours is started soon after the Handset is placed on the Charger Unit. Then it changes to Trickle charge to prevent from overcharging.
KX-TG5771BXS/KX-TGA570BXS 6 Installation Instructions 6.1. Setting up the Base Unit 6.2. Setting Up the Handset 6.1.1. Connecting the AC Adaptor and 6.2.1. Connecting the Charger Telephone Line Cord 6.3. Battery Installation/ Replacement 6.1.1.1. If you subscribe to a DSL service...
Battery Charge 6.4.1. Battery Level 6.4.2. Panasonic Battery Performance Note for service: The battery strength may not be indicated correctly if the battery is disconnected and connected again, even after it is fully charged. In that case, by recharging the battery as mentioned above, you will get a correct indication of the battery strength.
KX-TG5771BXS/KX-TGA570BXS 7.3. Dial Lock For Service Hint: *: If the current password is forgotten, enter “726276642” and you will be able to go to step 3.
KX-TG5771BXS/KX-TGA570BXS 8 Test Mode 8.1. Adjustment and Test Mode Flow Chart 8.1.1. Test Burst Mode for Base Unit Note: (*1) LCD displays the Channel number. (*2) Refer to Check Table for RF part (P.67) and RX-CW Test Mode for Handset (P.55) for proper Handset settings.
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KX-TG5771BXS/KX-TGA570BXS 8.1.2. RX-CW Test Mode for Base Unit Note: (*1) LCD displays the Channel number. (*2) Refer to Check Table for RF part (P.67) and Test Burst Mode for Handset (P.54) for proper Handset settings.
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KX-TG5771BXS/KX-TGA570BXS 8.1.3. Test Link Mode for Base Unit Note: (*1) LCD displays the Channel number. (*2) LCD displays the number of selected power. (*3) Refer to Test Link Mode for Handset (P.56). If can not proceed to the next step, refer to Registering a Handset (P.65).
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KX-TG5771BXS/KX-TGA570BXS 8.1.4. Adjustment Mode for Base Unit Cross Reference Check and Adjust X501 (Base Unit) Frequency (P.80) Note: (*1) This is an adjustment value (hex.).
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KX-TG5771BXS/KX-TGA570BXS 8.1.5. Test Burst Mode for Handset Note: (*1) LCD displays the Channel number. (exception: default/ CH00 = 1ch.) (*2) Refer to Check Table for RF part (P.67) and RX-CW Test Mode for Base Unit (P.51) for proper Base Unit settings.
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KX-TG5771BXS/KX-TGA570BXS 8.1.6. RX-CW Test Mode for Handset Note: (*1) LCD displays the Channel number. (exception: default/ CH00 = 1ch.) (*2) Refer to Check Table for RF part (P.67) and Test Burst Mode for Base Unit (P.50) for proper Base Unit settings.
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KX-TG5771BXS/KX-TGA570BXS 8.1.7. Test Link Mode for Handset Note: (*1) LCD displays the Channel number. (exception: default/ CH00 = 1ch.) (*2) If can not proceed to the next step, refer to Registering a Handset (P.65). (*3) for factory use only. (*4) Refer to Check Table for RF part (P.67) and Test Link Mode for Base Unit (P.52) for proper Base Unit settings.
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KX-TG5771BXS/KX-TGA570BXS 8.1.8. Adjustment Mode for Handset Cross Reference (*1) Adjust Battery Low Detector Voltage (Handset) (P.80) Note: (*2) These are the default values. (*3) These values may not be fixed depending on the battery strength.
KX-TG5771BXS/KX-TGA570BXS 9 Service Mode 9.1. How to Clear User Setting Units are reset to the Factory settings by this operation (Erase recorded Voice messages, stored Phone numbers, Caller list and etc.). This operation should not be performed for a usual repair.
KX-TG5771BXS/KX-TGA570BXS 10 Troubleshooting Guide 10.1. Troubleshooting Flowchart Cross Reference: Note: Check Power (P.60) (*1) When a user claims that the unit disconnects a call right Error Message Table (P.60) after the greeting message and no incoming messages can Check Playback (P.62) be recorded, this symptom can not be reappeared with TEL Check Record (P.61)
KX-TG5771BXS/KX-TGA570BXS 10.1.1. Check Power Cross Reference: Note: Power Supply Circuit (P.14) Flash Memory is IC601. Reset Circuit (P.16) DSP is IC501. (*1) Refer to Specifications (P.6) for part number and supply voltage of AC adaptor. 10.2. Error Message Table Display...
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KX-TG5771BXS/KX-TGA570BXS 10.2.1. Check Record BASE UNIT A) Not record Greeting Message B) Not record Incoming Message C) How to change the Auto Disconnect activation (time) Some Telephone Company lines (fiber or cable) ON Hook and OFF Hook voltages are lower than conventional lines, which may cause a malfunction of Auto Disconnect detection.
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KX-TG5771BXS/KX-TGA570BXS 10.2.2. Check Playback Cross Reference: Note: Power Supply Circuit (P.14) Flash Memory is IC601. DSP is IC501. 10.2.3. Check Sp-phone Transmission Cross Reference: Note: Signal Route (P.33) Flash Memory is IC601. Telephone Line Interface (P.17) DSP is IC501. 10.2.4. Check Sp-phone Reception...
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KX-TG5771BXS/KX-TGA570BXS 10.2.5. Check Battery Charge Note: Flash Memory is IC601. DSP is IC501. (*1) Refer to Specifications (P.6) for part number and supply voltage of AC adaptor.
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KX-TG5771BXS/KX-TGA570BXS 10.2.6. Check Link Note: Flash Memory is IC601. DSP is IC501. (*1) Refer to Finding out the Defective part (P.65). Cross Reference: Check the RF part (P.65)
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KX-TG5771BXS/KX-TGA570BXS 10.2.7. Check the RF part 10.2.7.1. Finding out the Defective part After All the Checkings or Repairing 1. Re-register the checked Handset to the checked Base Unit, and Regular HS to Regular BU. Note: (*1) HS: Handset (*2) BU: Base Unit...
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KX-TG5771BXS/KX-TGA570BXS 10.2.7.1.2. Deregistering a Handset 10.2.8. RF Check Flowchart Each item (1 ~ 6) of RF Check Flowchart corresponds to Check Table for RF part (P.67). Please refer to the each item.
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KX-TG5771BXS/KX-TGA570BXS 10.2.8.1. Check Table for RF part Item BU (Base Unit) Check HS (HandSet) Check Link Confirmation Normal 1. Register Regular HS to BU (to be 1. Register HS (to be checked) to Regular checked). HS, BU Mode [Normal Mode] 2.
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KX-TG5771BXS/KX-TGA570BXS 10.2.9. TEST RANGE Check Circuit block which range is defective can be found by the following check. Item BU (Base Unit) Check HS (HandSet) Check Range Confirmation TX TEST 1. Register Regular HS to BU (to be checked). 1. Register HS (to be checked) to Regular BU.
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KX-TG5771BXS/KX-TGA570BXS 10.2.9.1. RF-DSP Interface Signal Wave Form Test Burst Mode:...
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KX-TG5771BXS/KX-TGA570BXS Test Burst Mode:...
KX-TG5771BXS/KX-TGA570BXS 10.3. Check Handset Transmission Cross Reference: Signal Route (P.33). 10.4. Check Handset Reception Cross Reference: Signal Route (P.33). Note: When checking the RF part, Refer to Check the RF part (P.65) 10.5. Check Caller ID Cross Reference: Telephone Line Interface (P.17).
KX-TG5771BXS/KX-TGA570BXS 10.6. How to Replace the Flat Package IC Even if you do not have the special tools (for example, a spot heater) to remove the Flat IC, with some solder (large amount), a soldering iron and a cutter knife, you can easily remove the ICs that have more than 100 pins.
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KX-TG5771BXS/KX-TGA570BXS 10.6.3. How to Install the IC 1. Temporarily fix the FLAT PACKAGE IC, soldering the two marked pins. *Check the accuracy of the IC setting with the corresponding soldering foil. 2. Apply flux to all pins of the FLAT PACKAGE IC.
KX-TG5771BXS/KX-TGA570BXS 10.7. How to Replace the LLP (Leadless Leadframe Package) IC 10.7.1. Preparation • PbF (: Pb free) Solder • Soldering Iron Tip Temperature of 700°F ± 20°F (370°C ± 10°C) Note: We recommend a 30 to 40 Watt soldering iron. An expert may be able to use a 60 to 80 Watt iron where someone with less experience could overheat and damage the PCB foil.
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KX-TG5771BXS/KX-TGA570BXS 10.7.4. How to Install the IC 1. Place the solder a little on the land where the radiation GND pad on IC bottom is to be attached. 2. Place the solder a little on the land where IC pins are to be attached, then place the IC.
KX-TG5771BXS/KX-TGA570BXS 12 Measurements and Adjustments 12.1. Things to Do after Replacing IC 12.1.1. X501 (Base Unit), X201 (Handset) Check Equipment: Frequency counter Check Point for measurement: BCK Checking tolerance: 13.824 MHz ± 270 Hz (Base Unit)/13.824 MHz ± 100 Hz (Handset) 12.1.1.1.
KX-TG5771BXS/KX-TGA570BXS 12.2. Base Unit Reference Drawing When connecting the simulator equipment for checking, please refer to below. FL881 C891 C881 FL891 FL821 R813 FL811 C856 IC300 C857 Q141 Q142 Q161 Q156 PQUP11394Z Note: (*1) is referred to No.3 of Check Table for RF part (P.67)
KX-TG5771BXS/KX-TGA570BXS 12.3. Handset Reference Drawing When connecting the simulator equipment for checking, please refer to below. Note: (*1) is referred to No.3 of Check Table for RF part (P.67)
KX-TG5771BXS/KX-TGA570BXS 13 Schematic Diagram 13.1. For Schematic Diagram 13.1.1. Base Unit (Schematic Diagram (Base Unit_Main)) 13.1.1.1. Acoustic Testing Mode Notes: 1. DC voltage measurements are taken with voltmeter from the negative voltage line. 2. The schematic diagrams may be modified at any time with the development of new technology.
KX-TG5771BXS/KX-TGA570BXS 15 Appendix Information of Schematic Diagram 15.1. CPU Data (Base Unit) 15.1.1. IC501 Description High High_Z 60 KEY_IN6 Key In Description High High_Z 61 KEY_IN5 Key In GNDPA 62 KEY_IN4 Key In SPOUTP 63 KEY_IN3 Key In BCLK 64 KEY_IN2...
KX-TG5771BXS/KX-TGA570BXS 16.2. Cabinet and Electrical Parts (Handset) Note: (*1) Stick the MAGNETIC SHIELD (No. 124) to the exact location described above. (*2) Attach the SPACER (No. 128) to the exact location described above.
KX-TG5771BXS/KX-TGA570BXS 16.5. Replacement Parts List Note: Ref. Part No. Part Name & Description Remarks 1. RTL (Retention Time Limited) PQBC10473Y2 BUTTON, NAVIGATOR KEY ABS-HB The marking (RTL) indicates that the Retention Time is PQSX10322Z KEYBOARD SWITCH, MEMO limited for this item.
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KX-TG5771BXS/KX-TGA570BXS Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks CN101 K2LB102B0053 JACK R683 ERJ2GEJ821 CN301 K2ECYB000001 JACK R701 ERJ2RKF103X CN661 K1MY32BA0026 CONNECTOR R732 ERJ2GEJ100 (LCR FILTERS) R733 ERJ2GEJ100 FL811 J0E5797B0001 LCR FILTER...
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KX-TG5771BXS/KX-TGA570BXS Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks C601 ECJ0EB1A104K C856 ECJ0EC1H020C C660 ECUV1C104KBV C857 ECJ0EB0J105K C663 ECJ0EB1H102K 0.001 C865 ECUE1A333KBQ 0.033 C664 ECJ0EB1H102K 0.001 C871 F1G1HR10A561 0.1P C665 ECJ0EB1H102K 0.001...
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KX-TG5771BXS/KX-TGA570BXS 16.5.2.2. Main P.C. Board Parts Ref. Part No. Part Name & Description Remarks Note: (COMPONENTS PARTS) (*1) When you have replaced IC201 or IC241, adjust X201. RA201 D1H84724A013 RESISTOR ARRAY Refer to Check and Adjust X201 (Handset) Frequency RA251...
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KX-TG5771BXS/KX-TGA570BXS Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks C246 ECJ0EB1A104K C773 ECJ0EC1H101J 100P C261 ECUV1C104KBV C781 ECJ0EB1A104K C262 ECUV1A105KBV C782 ECJ0EC1H121J 120P C263 ECUV1A105KBV C801 ECJ0EC1H030C C271 ECUV1C474KBV 0.47 C802 ECJ0EC1H220J...
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KX-TG5771BXS/KX-TGA570BXS 16.5.4. Accessories and Packing Materials Note: (*1) You can download and refer to the Operating Instructions (Instruction book) on TSN Server. 16.5.4.1. KX-TG5771BXS Ref. Part No. Part Name & Description Remarks PQLV207BXZ AC ADAPTOR PQJA10075Z CORD, TELEPHONE PQJA10165Z CORD, AUDIO CABLE...