Panasonic KX-TC2000NZF, KX-TC2000NZB, KX-TC2000NZW manual Transmitter/Receiver, Base to Handset

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KX-TC2000NZB / KX-TC2000N ZW / KX-TC2000NZF

19.7. Transmitter/Receiver

Base Unit and Handset are mainly consists of RF(Radio Frequency) IC and CPU.

Base Unit and Handset transmit/receive voice signal and data signal through the antenna on carrier frequency.

Signal Pass :

*Refer to CDL TX/RX in Signal Route (P.46).

19.7.1. Base to Handset

Circuit Operation:

The voice signal input from the TEL LINE interface goes to RF IC as shown in

BLOCK DIAGRAM (BASE UNIT) (P.38).

In the talk mode (off-hook) condition, the telephone line voice signal passes through D2, D3, D4, D5, RY1 (Relay), R107 and T7.

The other party´s voice signal is coupled with T7 and amplified by Q11 and led to IC3-B (OP Amplifier device).

And the signal goes through the compressor of RF IC, it is output to transmitter circuit.

The signal of the data sent to the handset is applied in the anode of the variable capacitor diode (VARICAP : DV1).

The capacitor of VARICAP is changing in accordance with the voice signal from telephone line interface or TX DATA signal from CPU. Therefore, the carrier frequency which is generated by TXVCO will be changing, and Frequency modulated RF signal is generated and amplified by RF AMP(Q3, Q4, T5). It pass through the Duplexer DPX1 and radiated from Antenna.

The signal is transmitted from the base unit and received by the handset antenna and amplified by RF amplifier (Q1) through

DPX1 as shown in BLOCK DIAGRAM (HANDSET) (P.39). And then it is converted to 10.7 MHz and 455 KHz Intermediate frequency by RF IC and related components.

The demodulated audio signal is output from RF IC (DET OUT) and passed through "Expander" process to reduce noise, then voice signal amplified by "Receiver amplifier" is output to receiver (REC1).

The receiver loudness is adjustable using "LOUD" key on the handset. Q2 and Q3 control the volume. When CPU (VOL1) becomes low, the volume becomes "MID", while CPU (VOL1, 2) become low, the volume becomes "HIGH".

TX data (to Handset)

CPU (VTX) becomes low to turn on the transmission power transistor Q2, and CPU (TX-data) sends data signal. It is FM-modulated by TXVCO and driven by RF AMP, then transmitted to the handset.

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Contents KX-TC2000NZB KX-TC2000NZW KX-TC2000NZF Contents Cabinet and Electrical Parts Location Handet About Lead Free Solder PbF Pb free Suggested PbF SolderHow to recognize that Pb Free solder is used Base Unit Main PCBFor Service Technicians Battery Recharge Battery informationBattery Replacement Location of Controls Base Unit HandsetConnection For Service Hint Operations Making Calls Answering CallsKX-TC2000NZB / KX-TC2000N ZW / KX-TC2000NZF KX-TC2000NZB / KX-TC2000N ZW / KX-TC2000NZF Recall Button Disassembly Instructions Show in Fig Procedure To remove RemoveRear Cabinet Battery compartment cover Troubleshooting Guide Check Power Bell Reception Check Battery Charge Check Link CPU IC2 RF IC IC1Refer to Adjustment P.29 Check Handset Transmission Check Handset ReceptionAdjustments Base Unit Test Mode Flow Chart Base UnitHow to change the channel AdjustmentAdjustment Standard Base Unit IC1Adjustments Handset Test Mode Flow Chart HandsetHow to change the channel Adjustment IC1Adjustment Standard Handset Component ViewFlow Solder Side View Base Unit RF SpecificationHOW to Check the Handset Speaker Frequency Table MHz Explanation of CPU Data Communication STAND-BY TALK, Talk STAND-BYRinging Changing the Channel Ports for transmitting and receiving of data Block Diagram Base Unit RF IC IC1Block Diagram Handset IC2Circuit Operation OutlinePower Supply Circuit Reset Circuit Base Unit Dtmf Charge CircuitTelephone Line Interface Transmitter/Receiver Base to HandsetHandset to Base Signal Route Reset Circuit Handset Circuit Operation HandsetBattery Low / Power Down Detector 21.1. IC2 22.1. IC2 23.1. IC1 HOW to Replace Flat Package IC ProcedureModification Procedure of Bridge PreparationCabinet and Electrical Parts Location Base Unit Cabinet and Electrical Parts Location Handet Accessories and Packing Materials Replacement Parts List Cabinet and Electrical PartsDiodesi LED LED1 ERDS2TJ223 PQXA36ASVC Battery Accessories and Packing Materials Handset Schematic Diagram Handset For Schematic DiagramBase Unit Schematic Diagram Base Unit Schematic Diagram Base Unit 30.1 Base UnitRF Unit Base Unit FILTER\2Schematic Diagram Handset 31.2 RF Unit Handset IC1Memo Circuit Board Base Unit Component ViewFlow Solder Side View RX-VCO TX-VCOIC2 IC1 KXTC2000NZB