Panasonic KX-TC2000NZB, KX-TC2000NZW, KX-TC2000NZF manual Handset to Base

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

19.7.2. Handset to Base

Circuit Operation:

The voice signal from the handset user is picked up by the microphone (MC1), voice signal passes through "Compressor" process to reduce noise as shown in BLOCK DIAGRAM (HANDSET) (P.39). And the voice is FM-modulated by VARICAP (DV1).

The carrier frequency is generated by TX VCO. The transmitter power transistor Q4 is turned on/off by CPU (VTX). The carrier signal is amplified by RF AMP and sent to the handset duplexer and antenna.

The signal of 39MHz band (39.775~40.000MHz) which is input from ANT is filtered at DPX1 as shown in BLOCK DIAGRAM (BASE UNIT) (P.38), then it is input to RF IC.

The signal input to RF IC is converted through Mixer inside of RF IC, RF filter (CF1, CF2) and Expander.

The signal is transmitted from the handset and received by the base unit antenna and amplified by RF amplifier Q1, then it is converted to10.7 MHz and 450 KHz Intermediate by RF IC. The demodulated audio signal is output from RF IC (DET OUT) and passed through "Expander" process to reduce noise, then voice signal is led to LINE AMP. The signal is passed through TELEPHONE INTERFACE and Tel-line.

RX data (from Handset):

The data signal from handset (ex: Talk, ACK, COM) is also included in 39 MHz band same as the voice data. After second if filter, the data signal is made square shape by data limiting AMP of the RF IC. RX data is output to CPU (RX Data).

19.7.3. RF signal operation/control and PLL operation (RF UNIT)

Base unit radio frequency signal received by antenna passes through duplexer (DPX1).

RF signal is amplified by RF AMP. RF signal received from RF IC is mixed with RX local frequency at Mixer to generate

10.7 MHz wide band IF. The reference frequency is generated by X1 11.150 MHz crystal. VC1 is the reference frequency for adjustment. The 10.7 MHz is mixed with reference and 450KHz narrow band IF is generated. The demodulation audio signal is adjusted to the maximum at T1. RF IC is controlled by CPU (RF_STB, DATA, CLK). The RX local frequency is generated by RXVCO.

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Contents KX-TC2000NZB KX-TC2000NZW KX-TC2000NZF Contents Cabinet and Electrical Parts Location Handet Suggested PbF Solder About Lead Free Solder PbF Pb freeBase Unit Main PCB How to recognize that Pb Free solder is usedFor Service Technicians Recharge Battery information BatteryBattery Replacement Base Unit Handset Location of ControlsConnection For Service Hint Making Calls Answering Calls OperationsKX-TC2000NZB / KX-TC2000N ZW / KX-TC2000NZF KX-TC2000NZB / KX-TC2000N ZW / KX-TC2000NZF Recall Button Show in Fig Procedure To remove Remove Disassembly InstructionsRear Cabinet Battery compartment cover Troubleshooting Guide Check Power Bell Reception Check Battery Charge CPU IC2 RF IC IC1 Check LinkRefer to Adjustment P.29 Check Handset Reception Check Handset TransmissionTest Mode Flow Chart Base Unit Adjustments Base UnitAdjustment How to change the channelIC1 Adjustment Standard Base UnitTest Mode Flow Chart Handset Adjustments HandsetIC1 How to change the channel AdjustmentComponent View Adjustment Standard HandsetFlow Solder Side View RF Specification HOW to Check the Handset SpeakerBase Unit Frequency Table MHz STAND-BY TALK, Talk STAND-BY Explanation of CPU Data CommunicationRinging Changing the Channel Ports for transmitting and receiving of data RF IC IC1 Block Diagram Base UnitIC2 Block Diagram HandsetOutline Circuit OperationPower Supply Circuit Reset Circuit Base Unit Charge Circuit Telephone Line InterfaceDtmf Base to Handset Transmitter/ReceiverHandset to Base Signal Route Circuit Operation Handset Reset Circuit HandsetBattery Low / Power Down Detector 21.1. IC2 22.1. IC2 23.1. IC1 Procedure HOW to Replace Flat Package ICModification Procedure of Bridge PreparationCabinet and Electrical Parts Location Base Unit Cabinet and Electrical Parts Location Handet Accessories and Packing Materials Cabinet and Electrical Parts Replacement Parts ListDiodesi LED LED1 ERDS2TJ223 PQXA36ASVC Battery Accessories and Packing Materials For Schematic Diagram Base Unit Schematic Diagram Base UnitHandset Schematic Diagram Handset 30.1 Base Unit Schematic Diagram Base UnitFILTER\2 RF Unit Base UnitSchematic Diagram Handset IC1 31.2 RF Unit HandsetMemo Component View Circuit Board Base UnitRX-VCO TX-VCO Flow Solder Side ViewIC2 IC1 KXTC2000NZB
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