KX-T7730CA 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.
KX-T7730CA 4.2. Circuit Operations 4.2.1. 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.
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KX-T7730CA 4.2.2. 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.
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KX-T7730CA 4.2.3. 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.
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KX-T7730CA TONE Generation Circuit 4.2.4. 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.
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KX-T7730CA Handset Circuit 4.2.5. 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 2.
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KX-T7730CA Speakerphone Circuit 4.2.6. 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-T7730CA 8 Disassembly and Assembly Instructions 1. Remove the Stand. 2. Remove 4 Screws (A). 3. Remove the Bottom Cabinet. 4. Remove the Flat Cable from the Main Board.
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KX-T7730CA 5. Remove 5 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-T7730CA 9.2. How To Replace a Flat Package 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 sol- dering iron and a cutter knife, you can easily remove the ICs that have more than 100 pins.
MUTE STORE HS_MUTE SW52 SP_RX_MUTE L[7] R138 K[7] HOOK SP_TX_MUTE SP-PHONE Q108 R139 HS_POWER R140 SP_POWER R141 Q103 The handset is in use 4.7K 5.4V : Q103 The speakerphone is in use 0V : Q104 Q104 KX-T7730CA MAIN BOARD NO.1...
PAUSE FWD/DND CO10 SW13 AUTO ANS AUTO DIAL TRANSFER FLASH SW14 MUTE SW17 STORE SW18 SW19 SW20 SW46 SW23 SW24 SW25 SW33 SW26 SW50 SW43 SW48 REDIAL HOLD SP-PHONE KX-T7730CA MAIN BOARD BOTTOM VIEW 12 Appendix Information of Schematic Diagram...
KX-T7730CA 13 Exploded View and Replacement Parts List 13.1. IC1 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...
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KX-T7730CA Pin No. Terminal Name I/O Function I/O Setting Description LED2 LED3 LED4 LED5 LED6 LED7 HF SP vol 1 HF SP vol 2 HF SP vol 3 HF SP vol 4 Tone cont 1 Tone cont 2 Tone cont 3...
KX-T7730CA 13.4. Replacement Parts List Note: Ref. Part No. Part Name & Description Remarks 1. RTL (Retention Time Limited) L0CBAB000065 MICROPHONE The "RTL" marking indicates that its Retention Time is PSBX1102Z1 BUTTON, SP PHONE ABS- Limited. 94HB When production is discontinued, this item will continue to...
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KX-T7730CA Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks PSVTUMG2NTR TRANSISTOR(SI) F2G1C2200012 UN5213 TRANSISTOR(SI) PQCUV1A225ZF UN5213 TRANSISTOR(SI) ECUV1H102KBV 0.001 Q101 PQVTDTA143EU TRANSISTOR(SI) ECUV1H821KBV 820p Q102 2SC4081R TRANSISTOR(SI) ECUV1A224KBV 0.22 Q103 B1HBGBA00001 TRANSISTOR(SI)
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KX-T7730CA Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks C209 ECUV1H222KBV 0.0022 ERJ3GEYJ683 C211 ECUV1H103KBV 0.01 ERJ3GEYJ393 C212 ECUV1H102KBV 0.001 ERJ3GEYJ473 C213 ECUV1H102KBV 0.001 ERJ3GEYJ393 ERJ3GEYJ473 (RESISTORS) ERJ3GEYJ153 ERJ3GEYJ104 100k ERJ3GEYJ472 4.7k...