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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 WARNING This service information is designed for experienced repair technicians only and is not designed for use by the general public. It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to service a product. Products powered by electricity should be serviced or repaired only by experienced professional technicians.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 TABLE OF CONTENTS PAGE PAGE 1 Safety Precautions----------------------------------------------- 5 10.1.7. Registering a Handset to the Base Unit ------- 46 1.1. For Service Technicians --------------------------------- 5 10.1.8. Deregistering a Handset--------------------------- 46 2 Warning -------------------------------------------------------------- 5 10.1.9. Check Handset Transmission -------------------- 47 2.1.
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16.2. Cabinet and Electrical Parts (Handset) ------------- 90 16.3. Cabinet and Electrical Parts (Charger Unit) ------- 91 16.4. Accessories and Packing Materials ----------------- 92 16.4.1. KX-TG7841S ----------------------------------------- 92 16.4.2. KX-TG7842S ----------------------------------------- 93 16.4.3. KX-TG7843S ----------------------------------------- 94 16.4.4. KX-TG7844S ----------------------------------------- 95 16.4.5.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 1 Safety Precautions 1.1. For Service Technicians • Repair service shall be provided in accordance with repair technology information such as service manual so as to prevent fires, injury or electric shock, which can be caused by improper repair work. 1.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 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 manufacturer's specific instructions for the melting points of their products and any precautions for using their product with other materials.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4 Technical Descriptions 4.1. Circuit Configuration of TG78xx Series Phones TG78xx consists of DECT cordless telephone and Bluetooth Module. Both voices of transmission and reception are transferred by PCM. BBIC on DECT side controls the cordless telephone system, which makes control data communication with BT_IC on BT Module in serial data.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.2. US-DECT Description The frequency range of 1.92 GHz-1.93 GHz is used. Transmitting and receiving carrier between base unit and handset is same frequency. Refer to Frequency Table (P.66). 4.2.1. TDD Frame Format 5 ms 5 ms Up Link ( Handset - > Base Unit ) Down Link ( Base Unit - >...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.2.3. Signal Flowchart in the Radio Parts Reception Base unit: A voice signal from TEL line is encoded to digital data and converted into a 1.9GHz modulated radio signal by BBIC(IC501). The RF signal, after which is amplified in BBIC, is fed to selected antenna. Handset: As for a handset RF, RF signal is received in one antenna.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.4. Tel Interface Circuit...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.6. Circuit Operation (Base Unit) General Description: (BBIC, Flash Memory, EERROM) 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 BBIC system is fully controlled by a host processor. The host processor provides activation and control of all that functions as follows.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.6.6. Power Supply Circuit/Reset Circuit The power supply voltage from AC adaptor is converted to VBAT (3.0V) in IC302. And +3.0V for peripherals and analog part is insulated from VBAT by Doubler of BBIC. Circuit Operation: VDD4 +5.5V +3.0V VDD3 IC502 IC501...
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.6.6.1. Charge Circuit The voltage from the AC adaptor is supplied to the charge circuits. +5.5V F301 R373 CHARGE+ C351 CHARGE-...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.6.7. Telephone Line Interface Telephone Line Interface Circuit: Function • Bell signal detection • ON/OFF hook and pulse dial circuit • Side tone circuit Bell (RINGING) 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: L1T →...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.6.8. Parallel Connection Detect Circuit/Auto Disconnect 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.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.6.9. Calling Line Identification (Caller ID)/Call Waiting Caller ID Function: Caller ID 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.
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 Call Waiting Caller ID Calling Identity Delivery on Call Waiting (CIDCW) is a CLASS service that allows a customer, while off-hook on an existing call, to receive information about a calling party on a waited call. The transmission of the calling information takes place almost immediately after the customer is alerted to the new call so he/she can use this information to decide whether to take the new call.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.9. Circuit Operation (Handset) 4.9.1. Outline Handset consists of the following ICs as shown in Block Diagram (Handset) (P.21). • DECT BBIC (Base Band IC): IC1 - All data signals (forming/analyzing ACK or CMD signal) - All interfaces (ex: Key, Detector Circuit, Charge, EEPROM, LCD) •...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.9.3. Charge Circuit Circuit Operation: When charging the handset on the Base Unit, the charge current is as follows; DCP(5.5V) → F301 → R371 → R372 → D362 → CHARGE+(Base) → CHARGE+(Handset) → R8 → Q3 → F1 → BATTERY+... Battery...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 4.10. Behavior of Electric Power Failure In case that the power from AC adaptor is lost and lose radio waves, BBIC (IC1) turns Q11 ON since handset presumes that base unit's power is falied. Base unit detects that power voltage of AC adaptor +5.5V is OFF, then turns Q351 ON. It's possible to use the units during the power failure, supplying power to VBAT of base unit from battery of handset through Q10, CHG terminal and Q351.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 5 Location of Controls and Components Refer to the Operating Instructions. Note: You can download and refer to the Operating Instructions (Instruction book) on TSN Server. 6 Installation Instructions Refer to the Operating Instructions. Note: You can download and refer to the Operating Instructions (Instruction book) on TSN Server. 7 Operating Instructions Refer to the Operating Instructions.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 8 Test Mode 8.1. Engineering Mode 8.1.1. Base Unit Important: Make sure the address on LCD is correct when entering new data. Otherwise, you may ruin the unit. Soft keys {OFF} Navigator key/ (Volume) key Dial keypad {FLASH} {CALL WAIT} H/S LCD H/S key operation Phonebook...
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 Set Addr.: 7). Press , a long confirmation beep New Data will be heard. CLEAR 8). Press {OFF} to return to standby mode. Set Addr.: After that, turn the base unit power off and then power on. _ _ _ _ Note: * To enter "Set dial mode", press { } or {>} at "...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 8.1.2. Handset Important: Make sure the address on LCD is correct when entering new data. Otherwise, you may ruin the unit. Soft keys {OFF} Navigator key/ (Volume) key Dial keypad {FLASH} {CALL WAIT} H/S key operation H/S LCD 1). Press MENU Phonebook SELECT...
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 Frequently Used Items (Handset) ex.) Items Address Default Data New Data Possible Adjusted Possible Adjusted Remarks Value MAX (hex) Value MIN (hex) Battery Low 00 12/00 13 00 / 00 (*2) Frequency 00 07 / 00 08 00 / 01 00 02 ~ 00 06 Given value Note:...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 9 Service Mode 9.1. How to Clear User Setting (Handset Only) Handset Press simultaneously until a beep sound is heard. Then single handset is initialized. (The contents of user setting are reset to factory default) *Usage time is not cleared.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10 Troubleshooting Guide 10.1. Troubleshooting Flowchart FLOW CHART Not working Power ON Base Unit Check Power Not recording (*1) Record Check Record No playback Playback Pre-Message Check Playback Link No link Not charged Battery Charge Check Battery Charge Check Link Range Check the RF part No voice...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.1. Check Power 10.1.1.1. Base Unit Is the AC Adaptor inserted into AC outlet? (*1) AC Adaptor. Is output voltage of AC adaptor 5.5 V? Check Check Power Supply Circuit. Check VDD1(1.8V) :Test point (VDD1) RSTN: Reset = "High"? Check Reset Circuit.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.2. Check Record 10.1.2.1. Base Unit Not record Incoming Message Check Telephone Line Interface Check Bell signal. [Bell]. Check Telephone Line Interface Does the unit catch line? [OFF HOOK]. Check Line In: Pin 25 of BBIC. Check ICM Recording in Signal Route. Check Auto Disconnect Circuit.
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 <How to change the Auto Disconnect activation time and VOX level> A) 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. To solve this problem, try changing the Auto Disconnect activation through the procedures below.
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 B) Vox level: It makes easier to detect a small voice (caller) by raising the sensitivity of VOX level. Therefore, the recording of TAM is not turned off during detection. 1) ~ 2) are same as (A). 3) Press "5","1","1". Service ready :5 1 1 CLEAR...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.3. Check Playback 10.1.3.1. Base Unit Check VDD1(1.8V) :Test point (VDD1) Check Power Supply Circuit. Check output of BBIC (Pin 41,43). Check BBIC and Flash Memory. Check Speaker and its surroundings. Cross Reference: Note: Power Supply Circuit/Reset Circuit (P.15) Flash Memory is IC601.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.5. Check Link 10.1.5.1. Base Unit Does Base Unit connect to the properly working Base Unit is OK. Check Handset. Handset? Is the voltage of VDD3 about 3.0V? Check around Power Supply Circuit. Is the voltage of VDD1 about 1.8V? Check around X501 and RF module and adjust Does the RF clock (CLK) oscillate at 10.368 MHz in Base Unit Test Mode?
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.5.2. Handset Does Handset link with Base Unit? Handset is OK. Check Base Unit. (Properly working unit) Is the voltage of TP VBAT about 2.2~2.8 V? Check the batteries. Check around Power Supply Circuit/Reset Circuit. Is the voltage of TP VDDC about 1.2 V? Is the voltage of TP 3.0 V about 3.0 V? Does the RF clock (CLK) oscillate: 13.824 MHz Check around X1 and RF module and adjust...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.6. Check the RF part 10.1.6.1. Finding out the Defective part 1. Prepare Regular HS(*1) and Regular BU(*2). 2. a. Re-register regular HS (Normal mode) to base unit (to be checked). If this operation fails in some ways, the base unit is defective. b.
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.6.2. RF Check Flowchart Each item (1 ~ 5) of RF Check Flowchart corresponds to Check Table for RF part (P.44). Please refer to the each item. Start Link Control Check BBIC interface parts. confirmation signal (RF Block <->BBIC on BU/HS P.C.B) Normal confirmation X'tal...
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.6.3. 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-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.6.4. 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. (TX Power check) 2.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.7. Registering a Handset to the Base Unit The supplied handset and base unit are pre-registered. If for some reason the handset is not registered to the base unit, re-register the handset. 1 Handset: {MENU} i # 1 3 0 2 Base unit: Press and hold {LOCATOR} for about 5 seconds until the registration tone sounds.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.9. Check Handset Transmission Check MIC of handset. Check handset Tx in Signal Route. Cross Reference: Signal Route (P.26) 10.1.10. Check Handset Reception Check speaker of handset. Check handset Rx in Signal Route. Cross Reference: Signal Route (P.26) Note: When checking the RF part, Refer to Check the RF part (P.42).
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 10.1.12. Check BT Communication Plug in the AC power source and wait 10 seconds. Use a handset to enter the "Bluetooth" menu: Press [MENU] Bluetooth [SELECT] Is it possible to enter the "Bluetooth" menu? Check the circuit of around RF parts of BT Is it possible to register BT_Headset? Module Check Voice Transmission of the BT_Headset...
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 Case1: OK AC power on PIO01 0.05s 1.95s 1.5s Case2: NG1(fail to reset BT_IC) AC power on If BT_IC does not work, 1st and 2nd signals does not appear. Check the circuit of around PIO01 POWER and RESET parts of BT Module.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 11 Disassembly and Assembly Instructions 11.1. Disassembly Instructions 11.1.1. Base Unit Remove the 5 screws to remove the cabinet cover. Remove the solders. Cabinet cover Solders Remove the pararell wire to remove the main P.C. board.
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 Remove the 2 screws to remove the Jack holder. Remove the 4 screws to remove the operational P.C.B board.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 11.1.2. Handset 2 screws Remove the 2 screws. Insert a JIG (PQDJ10006Y) between the cabinet body Cabinet body and the cabinet cover, then pull it along the gap to open the cabinet. Cabinet cover Likewise, open the other side of the cabinet. Cabinet cover Remove the cabinet cover by pushing it upward.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 11.2. How to Replace the Base unit LCD Fit the heatseal of a new LCD. Vertical Interval Tolerance 0.2mm Horizontal Interval Tolerance 0.2mm If interval tolerance between center lines is less than 0.2 mm, it is o.k. New LCD Operational P.C.B.
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 Attach the LCD and fix by hook A (two points). Solder the wires.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 11.3. How to Replace the Handset LCD Note: The illustrations are simplified in this page. They may differ from the actual product. P. C. board Vertical Interval Tolerance Peel off the FFC (Flexible Flat Cable) from 0.2 mm the LCD, in the direction of the arrow. Take care to ensure that the foil on the P.C.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 12 Measurements and Adjustments This chapter explains the measuring equipment, the JIG connection, and the PC setting method necessary for the measurement in Troubleshooting Guide (P.34) 12.1. Equipment Required • Digital multi-meter (DMM): it must be able to measure voltage and current. •...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 12.2.2. Connections (Handset) Connect the DC Power or Battery to BATT+ and BATT-. Connect the JIG cable GND (black) to GND. Connect the JIG cable UTX (yellow) to UTX and URX (red) to URX. URX (red) To Serial Port UTX (yellow) (com port 1*) GND (black)
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 12.2.3. How to install Batch file into P.C. Insert the Batch file CD-ROM into CD-ROM drive and copy PNZZTG**** folder to your PC (example: D drive). <Example for Windows> On your computer, click [Start], select Programs Open an MS-DOS mode window. (All Programs for Windows XP/Windows Server 2003), then click MS-DOS Prompt.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 12.2.4. Commands See the table below for frequently used commands. Command name Function Example rdeeprom Read the data of EEPROM Type “rdeeprom 00 00 FF”, and the data from address “00 00” to “FF” is read out. readid Read ID (RFPI) Type “readid”, and the registered ID is read out.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 12.5. Things to Do after Replacing IC or X'tal If repairing or replacing EEPROM and X'tal, it is necessary to download the required data such as Programming data or adjustment data, etc. in memory. The set doesn't operate if it is not executed. 12.5.1.
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK Items How to download/Required adjustment BBIC(IC501) Programming data is stored in memory. 1) Clock adjustment: Refer to Check Point (H).(*2) EEPROM (IC611) Adjusted parameter data is stored in memory. 1) Change the address “0001” of EEPROM to “AA” to download (country version batch file, default batch file, the data.
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 12.5.1.2. Handset First, operate the PC setting according to The Setting Method of JIG (P.57). Then download the appropriate data according to the following procedures. Items How to download/Required adjustment EEPROM (IC3) Adjusted parameter data is stored in memory. 1) Default batch file: Execute the command “default.bat”.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 13 Miscellaneous 13.1. How to Replace the LLP (Leadless Leadframe Package) IC Note: This description only applies to the model with Shield case. 13.1.1. 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.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 13.1.4. 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. Soldering Iron Land Solder P.C.Board 2. Place the solder a little on the land where IC pins are to be attached, then place the IC. Note: •...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 13.2. 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. 13.2.1.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 13.2.3. 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. 3.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 14 Schematic Diagram 14.1. For Schematic Diagram 14.1.1. Base Unit (Schematic Diagram (Base Unit_Main)) Notes: 1. DC voltage measurements are taken with voltmeter from the negative voltage line. Important Safety Notice: Components identified by mark have special characteristics important for safety.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 16 Exploded View and Replacement Parts List 16.1. Cabinet and Electrical Parts (Base Unit) E1 (*1) PCB1 PCB2 MIC1 PCB3 (*3) 26 (*2) 19 (*3) Ref.No. Figure 2.6 x 8mm Note: (*1) This cable is fixed by heat-sealing. Refer to How to Replace the Base unit LCD (P.54). (*2) KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK (*3) KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK...
(*1) This cable is fixed by heat-sealing. Refer to How to Replace the Handset LCD (P.56). (*2) The rechargeable Ni-MH battery HHR-4DPA is available through sales route of Panasonic. (*3) Attach the SPACER (No. 118) to the exact location described above.
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 16.4.2. KX-TG7842S A101 A102 P102 P102 (*1) P102 A105 A103, A104 P101 Note: (*1) This pad is a piece of Ref No.P101 (GIFT BOX).
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 16.4.13. KX-TGA680S A1202 (*1) P1202 A1201 P1201 Note: (*1) This pad is a piece of Ref No.P1201 (GIFT BOX).
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 16.5. Replacement Parts List Safety Ref. Part No. Part Name & Description Remarks 1. RTL (Retention Time Limited) PQHR11082Z GUIDE, SPEAKER POM-HB PNKE1272Z2 CASE, CHARGE TERMINAL PS-HB Note: PNJT1144Z CHARGE TERMINAL The “RTL” marking indicates that its Retention Time is PNBC1486Z1 BUTTON, NAVIGATOR KEY ABS-HB...
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KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 16.5.1.2. Main P.C. Board Parts Safety Ref. Part No. Part Name & Description Remarks Note: RA653 D1H810240004 RESISTOR ARRAY (*1) When replacing IC501, IC502, IC601, IC611 or X501, RA654 D1H810240004 RESISTOR ARRAY make the adjustment using PNZZTG7871M. Refer to How RA655 EXB28V473JX RESISTOR ARRAY...
INSTRUCTION BOOK (*1) Instructions (Instruction book) on TSN Server. A504 PNQW3431Z LEAFLET, QUICK GUIDE A505 PNKE1268Z1 HANGER, BELT CLIP ABS-HB 16.5.4.1. KX-TG7841S 16.5.4.7. KX-TG7871S Safety Ref. Part No. Part Name & Description Remarks Safety Ref. Part No. Part Name & Description Remarks...
KX-TG7841/KX-TG7842/KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680 Safety Ref. Part No. Part Name & Description Remarks Safety Ref. Part No. Part Name & Description Remarks A802 PQJA10075Z CORD, TELEPHONE PNZZTG7871M BATCH FILE CD-ROM (*1) A803 PNQX5764Z INSTRUCTION BOOK (*1) PQZZ430PIR TIP OF SOLDERING IRON (*2) A804 PNQW3431Z LEAFLET, QUICK GUIDE PQZZ430PRB...
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KX-TG7841/KX-TG7842KX-TG7843/KX-TG7844/KX-TG7845/KX-TG365SK/KX-TG7871/KX-TG7872/KX-TG7873/KX-TG7874/KX-TG7875/KX-TG385SK/KX-TGA680/KX-TGA20 TABLE OF CONTENTS PAGE 1 REPLACEMENT PARTS LIST ---------------------------------3 1.1. REFERENCE CHART ------------------------------------3 1.2. ORIGINAL AND NEW PARTS COMPARISON LISTS ------------------------------------3...
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Part Name & Description Pcs/ Remarks Notes Time of Change Original (Old) (Suffix) Cabinet and Electrical Parts (Base Unit) PNGT7152Z PNGT7732Z NAME PLATE (for KX-TG7841S/ TG7842S/TG7843S/TG7844S/ TG7845S/TG365SK) PNGT7261Z PNGT7677Z NAME PLATE (for KX-TG7871S/ TG7872S/TG7873S/TG7874S/ TG7875S/TG385SK) (Made in China) ---------- PNGT7854Z...