KX-T7730X CONTENTS Page Page 1 INTRODUCTION 8.5. THE ELECTRONIC VOLUME OF THE SPEAKER-PHONE 1.1. NOTE DOES NOT WORK 1.2. FOR SERVICE TECHNICIANS 8.6. THE ELECTRONIC VOLUME OF HANDSET DOES NOT 2 LOCATION OF CONTROLS WORK 3 CONNECTION 9 TERMINAL GUIDE OF ICS, TRANSISTORS AND DIODES...
KX-T7730X 1 INTRODUCTION 1.1. NOTE When you note the serial number, write down all of the 11 digits. The serial number may be found on the label affixed to the bottom of the unit. 1.2. FOR SERVICE TECHNICIANS ICs and LSIs are vulnerable to static electricity.
KX-T7730X 4 DISASSEMBLY INSTRUCTIONS 1. Remove the Stand. 2. Remove 4 Screws (A). 3. Remove the Bottom Cabinet. 4. Remove the Connector (1~3) and the Flat Cable from the Main Board.
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KX-T7730X 5. Remove 2 Screws (A). 6. Remove the Main Board from the Top Cabinet. 7. Remove the Cable from the Main Board. 8. Remove the LCD Holder by sliding the Hook in the direction of the arrow from the Main Board.
KX-T7730X 5 IC DATA Pin No. Terminal Name I/O Function I/O Setting Description LCD linage H:3line Model L:Other TEST Vcc Connection OSC1 4MHz OSC2 4MHz RESET Not used Vcc Connection Open HS SM mute HF MM mute O( I ) HF SM mute(This is also model code.)
KX-T7730X 7 CIRCUIT OPERATIONS 7.1. KEY INPUT CONTROL CIRCUIT Sequential input information is executed by dynamic scanning. The ports R20~R23, R30, R31 of IC1 are brought to high status consecutively. If a key is pressed, the key-in information input is executed by ports R00~R03, R10~R13.
KX-T7730X 7.2. LED CIRCUIT Circuit Operation: The LED executes dynamic lighting for the status indicators, and control is executed by the output ports R20~R23, R60~R63, R70~R73.
KX-T7730X 7.3. DATA COMMUNICATION CIRCUIT Function: The data communication circuit serves the following functions: Information exchanger between the PBX and proprietary telephone, key input information as well as data for the LED control, LCD control, etc. This information is continuously exchanged at all times.
KX-T7730X 7.4. TONE GENERATION CIRCUIT Function: This circuit generates all system tones including COL, extension, busy, DTMF signals and key in confirmation tones during the power failure mode and is comprised of IC1(DTMF Generator) and IC5 (Analog Switch). Circuit Operation: For an output of a single row tone, the row terminal and the each column terminals intersecting with it are required to be brought a low state.
KX-T7730X 7.5. HANDSET CIRCUIT 1) Transmission Signal Path The input signal for the handset microphone is sent through the telephone line via the following path: Handset MIC(JK2) → JK3 → C24 → R26 → C34 → Q5 → C21 → R21 → Q3 → C4 → T1 → C3 → Q1 → D1 → Telephone Line...
KX-T7730X 7.6. SPEAKERPHONE CIRCUIT Function: This circuit controls the automatic switching of the transmitted and received signals to and from the telephone line, when the unit is used in the hands-free mode. Circuit Operation: The speakerphone can only provide a one-way communication path at a given time, but cannot do both simultaneously.
KX-T7730X 10 HOW TO REPLACE THE FLAT PACKAGE IC If you do not have the special tools (for example: SPOT HEATER) to remove the SPOT HEATER’S Flat IC, If you have solder (large amount) a soldering iron and a cutter knife, you can easily remove IC’s even though large than 100 pin.
KX-T7730X 10.3. FLAT PACKAGE IC INSTALLATION PROCEDURE 1. Temporary fix FLAT PACKAGE IC by soldering on two marked pins. *Check the accuracy of the IC setting with the corresponding soldering foil. 2. Apply flux for all pins of FLAT PACKAGE IC.
KX-T7730X 13 REPLACEMENT PARTS LIST Note: Ref. Part No. Part Name & Remarks Description 1. RTL (Retention Time Limited) PSUS1018Z SPRING The marking (RTL) indicates that the Retention Time is PSBH1007Z1 BUTTON, HOOK PC+ABS-94HB PSHG1122Z RUBBER PARTS, MIC limited for this item.
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KX-T7730X Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks PSVTUMG2NTR TRANSISTOR(SI) ECUV1H102KBV 0.001 B1ABGB000020 TRANSISTOR(SI) ECUV1H821KBV 820p B1ABGB000020 TRANSISTOR(SI) ECUV1C224KBV 0.22 PSVTUMG2NTR TRANSISTOR(SI) ECEV0JA101 PSVTUMG2NTR TRANSISTOR(SI) UN5213 TRANSISTOR(SI) ECUV1H222KBV 0.0022 UN5213 TRANSISTOR(SI) ECUV1C473KBV 0.047...
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KX-T7730X Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks C109 ECUV1H120JCV ERJ3GEY0R00 C110 ECUV1C104ZFV ERJ3GEYJ224 220k ERJ3GEYJ124 120k C201 PSCEV1HA100 ERJ3GEYJ563 C203 PSCEV1EA470S C204 ECUV1C104ZFV ERJ3GEYJ273 C205 ECEV0JA101 ERJ3GEYJ473 C206 PSCEV0JA102 1000...
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KX-T7730X Ref. Part No. Part Name & Description Remarks (PHOTO ELECTRIC TRANSDUCER) 0N3181 PHOTO COUPLER (SWITCH) PSSS3A101Z SWITCH (TRANSFORMERS) G5A1A0000003 TRANSFORMER PSLT9Z4A TRANSFORMER (CRYSTAL OSCILLATOR) H0J400400011 CRYSTAL OSCILLATOR...
KX-T7730X 14 FOR THE SCHEMATIC DIAGRAM Note: 1. DC voltage measurements are taken with an oscilloscope or a tester with a ground. 2. The schematic diagrams and circuit board may be modified at any time with the development of new technology.
FWD/DND MUTE STORE HS_MUTE SW52 SP_RX_MUTE L[7] R138 HOOK K[7] SP-PHONE SP_TX_MUTE R139 HS_POWER R140 SP_POWER R141 The handset is in use Q103 5.4V : Q103 The speakerphone is in use 0V : Q104 Q104 4.7K KX-T7730X MAIN BOARD NO.1...