Kenwood-TK-2107-Service-Manual电路原理图.pdf

© 2000-05 PRINTED IN JAPANB51-8536-00(S) 200VHF FM TRANSCEIVERTK-2107SERVICE MANUALGENERAL. 2REALIGNMENT . 2DISASSEMBLY FOR REPAIR . 4CIRCUIT DESCRIPTION . 5SEMICONDUCTOR DATA . 9DESCRIPTION OF COMPONENTS . 10PARTS LIST. 11EXPLODED VIEW . 17PACKING . 18ADJUSTMENT. 19PC BOARD VIEWSTX-RX UNIT (X57-6020-21) . 23SCHEMATIC DIAGRAM . 27BLOCK DIAGRAM . 31LEVEL DIAGRAM . 33KNB-15A (Ni-Cd BATTERY) . 34SPECIFICATIONS . BACK COVERAntenna(T90-0733-05):M3Cabinet assy(A02-2448-13)Knob(VOLUME)(K29-5255-03)TK-2107 (16 channels)CONTENTSKnob(CHANNEL SELECTOR)(K29-5278-03)2TK-2107TK-260 :K, K2MODE FUNCTIONUser Mode Use this mode for normal operation.PC Mode Use this mode, to make varioussettings by means of the FPU throughthe RS-232C port.Manufacture Mode Use this mode, to realign the varioussettings through the RS-232C portduring manufacture work.2 How to enter each modeMODE PROCEDUREUser Mode Power ONPC Mode Connect to the IBM PC compatiblemachine and controled by the FPU.INTRODUCTIONSCOPE OF THIS MANUALThis manual is intended for use by experienced techniciansfamiliar with similar types of commercial gradecommunications equipment. It contains all required serviceinformation for the equipment and is current as of thepublication data. Changes which may occur after publicationare covered by either Service Bulletins or Manual Revisions.These are issued as required.ORDERING REPLACEMENT PARTSWhen ordering replacement parts or equipmentinformation, the full part identification number should beincluded. This applies to all parts : components, kits, orchassis. If the part number is not known, include the chassis orkit number of which it is a part, and a sufficient description ofthe required component for proper identification.GENERAL/REALIGNMENT3 Getting acquaintedPC ModeUser Mode Manufacture ModeSpeakerAntennaSpeaker/microphonejacksPTT (Push-To-Talk) switchPress this switch, then speak into the microphone tocall a station. Release the switch to receive.Monitor keyPress and hold to monitor how busy the currentchannel is and to monitor signals being received thatdo not contain the matched QT/DQT code.Channel selectorRotate to select channels 1 16.LED indicatorLights red while transmitting, green while receiving asignal. Flashes red when the battery voltage is lowwhile transmitting.Power switch/ Volume controlTurn clockwise to switch the transceiver ON. Turncounterclockwise until a click sounds, to switch thetransceiver OFF. Rotate to adjust the volume level.MicrophoneDestnation Number of CH RF power outputM3 16 5WPERSONAL SAFETYThe following precautions are recommended for personalsafety : DO NOT transmit until all RF connectors are verified secureand any open connectors are properly terminated. SHUT OFF and DO NOT operate this equipment nearelectrical blasting caps or in an explosive atmosphere. This equipment should be serviced by a qualifiedtechnician only.SERVICEThis radio is designed for easy servicing. Refer to theschematic diagrams, printed circuit board views, andalignment procedures contained within.REALIGNMENT1 Modes3TK-2107TK-260 :K, K2REALIGNMENTPC MODEPrefaceThe transceiver is programmed by using a personalcomputer, programming interface (KPG-22) and programmingsoftware (KPG-55D).The programming software can be used with an IBM PC orcompatible. Figure 1 shows the setup of an IBM PC forprogramming.Connenction procedure1. Connect the TK-2107 to the personal computer with theinterface cable.2. When data is transmitting from the transceiver the red LEDlights.When data is receiving by the transceiver the green LEDlights.Notes: The data stored in the personal computer must match theModel Name when it is written into the EEPROM. Do not press the PTT key during data transmission orreception.Fig. 1IBM-PCKPG-55DGray SPMICGray/Black 1.5D-XV Lead wire1.5D-XV Shield wire Tuning cable(E30-3216-05)KPG-22RF Power meteror SSG-+-+ KPG-22 description(PC programming interface cable: Option)The KPG-22 is required to interface the TK-2107 with thecomputer. It has a circuit in its D-subconnector (25-pin) casethat converts the RS-232C Iogic level to the TTL Ievel. TheKPG-22 connects the side panel jacks of the TK-2107 to thecomputer's RS-232C serial port. Programming software descriptionThe KPG-55D Programming Disk is supplied in 3-1/2“ the diskformat. The Software on this disk allows a user to programTK-2107 radios via a Programming interface cable (KPG-22). Programming with IBM PCIf data is transferred to the transceiver from an IBM PC withthe KPG-55D, the destination data (basic radio information)for each set can be modified. Normally, it is not necessary tomodify the destination data because their values aredetermined automatically when the frequency range(frequency type) is set.The values should be modified only if necessary.Data can be programmed into the EEPROM in RS-232Cformat via the SP MIC plug.In this mode the PTT Iine operates as TXD and RXD datalines respectively.* M3 type has wide mode only.All narrow data should be not available, even thouth data wouldbe modified in test mode.4TK-2107TK-260 :K, K2DISASSEMBLY FOR REPAIRSeparating the case assembly from the chassis1. Remove the two knobs and three round nuts .2. Remove the two screws .3. Expand the right and left sides of the bottom of the caseassembly, Iift the chassis, and remove it from the caseassembly .4. Taking care not to cut the speaker lead , open the chassisand case assembly.Separating the chassis from the unit1. Remove the eleven screws .2. Remove the solder from the antenna terminal using asoldering iron then lift the unit off .3. Remove the two screws and remove the antennaconnector.Note : When reassembling the unit in the chassis, be sure tosolder the antenna terminal.Removing the lever1. Raise the lever on the lower case , insert a small flatscrewdriver into the space between the case and lever,open the case carefully and lift the lever off.Note : Do not force to separate the case from the lever.Lever knobCace assemblyAntenna terminal5TK-2107TK-260 :K, K21. Frequency configurationThe receiver utilizes double conversion. The first IF is38.85MHz and the second IF is 450kHz. The first localoscillator signal is supplied from the PLL circuit.CIRCUIT DESCRIPTIONANTANT SWRFAMPMCFCFIF SYSTEMAFAMPRXTXPAAMPTXAMPPLLVCOMICAMPTCXOX3multiply38.85MHz450kHz38.4MHz12.8MHzSPMICFig. 1 Frequency configurationANTD102, D103BPFRF AMPQ203 BPFMIXERQ202MCFXF200IF AMPQ201CF200IF, MIX, DETIC200AF AMPLPF, HPFIC300AF PA AMPIC302SPX3multiplyQ1TCXO1st Local OSC(PLL)ANT SWFig. 2 Receiver section configurationThe PLL circuit in the transmitter generates the necessaryfrequencies. Fig. 1 shows the frequencies.2. ReceiverThe receiver is double conversion superheterodyne,designed to operate in the frequency range of 216 to 223MHz(M3 type).The frequency configuration is shown in Fig. 1.1) Front - end RF amplifierAn incoming signal from the antenna is applied to an RFamplifier (Q203) after passing through a transmit/receiveswitch circuit (D102 and D103 are off) and a band pass filter(L208, L209 and L210). After the signal is amplified (Q203),the signal is filtered through a band pass filter (L203 and L214)to eliminate unwanted signals before it is passed to the firstmixer. (See Fig. 2)2) First MixerThe signal from the RF amplifier is heterodyned with thefirst local oscillator signal from the PLL frequency synthesizercircuit at the first mixer (Q202) to create a 38.85MHz firstintermediate frequency (1st IF) signal. The first IF signal isthen fed through two monolithic crystal filters (MCFs : XF200)to further remove spurious signals.3) IF amplifierThe first IF signal is amplified by Q201, and then entersIC200 (FM processing IC). The signal is heterodyned againwith a second local oscillator signal within IC200 to create a450kHz second IF signal. The second IF signal is then fedthrough a 450kHz ceramic filter (CF200) to further eliminateunwanted signals before it is amplified and FM detected inIC200.4) AF amplifierThe recovered AF signal obtained from IC200 is amplifiedby IC300 (1/4), filtered by the IC300 low-pass filter (2/4) andIC300 high-pass filter (3/4) and (4/4), and de-emphasized byR303 and C306. The processed AF signal passes through anAF volume control and is amplified to a sufficient level to drivea loud speaker by an AF power amplifier (IC302).6TK-2107TK-260 :K, K2Item RatingNominal center frequency 38.850MHzPass band width 7.5kHz or more at 3dB40dB stop band width 40.0kHz or lessRipple 1.0dB or lessInsertion loss 3.0dB or lessGuaranteed attenuation 80dB or more at fo -1000kHzTerminal impedance 1200W / 1.4PFItem RatingNominal center frequency 450kHz6dB band width 7.5kHz or more50dB band width 15kHz or lessRipple 2.0dB or less at fo 5kHzInsertion loss 6.0dB or lessGuaranteed attenuation 35.0dB or more at fo 100kHzTerminal impedance 1.5 kWXF200:L71-0535-05 CF200:L72-0979-055) SquelchPart of the AF signal from the IC enters the FM IC again,and the noise component is amplified and rectified by a filterand an amplifier to produce a DC voltage corresponding to thenoise level.The DC signal from the FM IC goes to the analog port of themicroprocessor (IC403). IC403 determines whether to outputFig. 3 AF Amplifier and squelchFM IF IC IC200IF AMP DETDETHPFAMPLPFIC301QT/DQTQ303W/N SWIC403MPUBUSYMUTE AFCOTI6 567 62AF AMPIC300LPF HPFQ302SWIC302AF PA AMPQ307SWSWSPQ304, 305, 306sounds from the speaker by checking whether the inputvoltage is higher or lower than the preset value.To output sounds from the speaker, IC403 sends a highsignal to the MUTE and AFCO Iines and turns IC302 onthrough Q302, Q304, Q305, Q306 and Q307.(See Fig. 3)6) Receive signalingQT/DQT300 Hz and higher audio frequencies of the output signalfrom IF IC are cut by a low-pass filter (IC301). The resultingsignal enters the microprocessor (IC403). IC403 determineswhether the QT or DQT matches the preset value, andcontrols the MUTE and AFCO and the speaker output soundsaccording to the squelch results.3. PLL frequency synthesizerThe PLL circuit generates the first local oscillator signal forreception and the RF signal for transmission.1) PLLThe frequency step of the PLL circuit is 5 or 6.25kHz.A 12.8MHz reference oscillator signal is divided at IC1 by a fixedcounter to produce the 5 or 6.25kHz reference frequency. Thevoltage controlled oscillator (VCO) output signal is bufferamplified by Q6, then divided in IC1 by a dual-moduleprogrammable counter . The divided signal is compared in phasewith the 5 or 6.25kHz reference signal in the phase comparator inIC1. The output signal from the phase comparator is filtreredthrough a low-pass filter and passed to the VCO to control theoscillator frequency. (See Fig.4)CIRCUIT DESCRIPTION7TK-2107TK-260 :K, K2Fig. 4 PLL circuitFig. 6 Transmit audio QT/DQT3) UNLOCK DETECTORIf a pulse signal appears at the LD pin of IC1, an unlockcondition occurs, and the DC voltage obtained from D7, R6,and C1 causes the voltage applied to the UL pin of themicroprocessor to go low. When the microprocessor detectsthis condition, the transmitter is disabled, ignoring the push-to-talk switch input signal. (See Fig.5)4. Transmitter1) Transmit audioThe modulation signal from the microphone is amplified byIC500 (1/2), passes through a preemphasis circuit, andamplified by the other IC500 (1/2) to perform IDC operation.The signal then passes through a low-pass filter (splatter fiIter)(Q501 and Q502) and cuts 3kHz and higher frequencies. Theresulting signal goes to the VCO through the VCO modulationterminal for direct FM modulation. (See Fig. 6)Fig. 5 Unlock detector circuitIC1LDPLL ICD7C1R65CIC403ULMPUPLL DATA12.8MHzREF OSCI/MI/NPLL IC IC1PHASECOMPARATORCHARGEPUMPLPF5kHz/6.25kHzD1, 2D3, 4Q4TX VCOQ3RX VCOQ6BUFF AMPQ2RF AMPQ5, 7T/R SW5kHz/6.25kHzMUTEVR501MAXDEVBALANCEX1, IC1D5, Q4VCOREFERENCEOSC(TCXO)MICIC500 (1/2)MICAMPIC500 (1/2)IDCQ503SWPREEMPHASISQ501, 502LPF(SPLATTER FILTER)IC403TOQT/DQT2) VCOThe operating frequency is generated by Q4 in transmitmode and Q3 in receive mode. The oscillator frequency iscontrolled by applying the VCO control voltage, obtained fromthe phase comparator, to the varactor diodes (D2 and D4 intransmit mode and D1 and D3 in receive mode). The T/R pin isCIRCUIT DESCRIPTIONset high in receive mode causing Q5 and Q7 to turn Q4 off,and turn Q3 on . The T/R pin is set low in transmit mode. Theoutputs from Q3 and Q4 are amplified by Q6 and sent to thebuffer amplifiers.2) QT/DQT encoderA necessary signal for QT/DQT encoding is generated byIC403 and FM-modulated to the PLL reference signal. Sincethe reference OSC does not modulate the loop characteristicfrequency or higher, modulation is performed at the VCO sideby adjusting the balance. (See Fig. 6)8TK-2107TK-260 :K, K2CIRCUIT DESCRIPTION3) VCO and RF amplifierThe transmit signal obtained from the VCO buffer amplifierQ100, is amplified by Q101. This amplified signal is passed tothe power amplifier, Q102 and Q105, which consists of a 2-stage FET amplifier and is capable of producing up to 5W ofRF power. (See Fig.7)Fig. 7 APC systemK41K4DK50K51K31K30K31K44K52K49K56K45K41K4DK50K51K31K30K32K35K54K42K51K31K30K33K2C K51K31K30K34K42K53K57K44K45K54K49K43K31K30K30K41K50K43K35K54K51K31K30K39K53K57K51K31K30K36K53K57K41K50K43K35K54K51K31K30K38K53K57K52K58K44K31K30K32K2CK31K30K33K41K4EK54 K53K57K46K49K4EK41K4CK41K4DK50K51K31K30K35K41K4EK54 K53K57K44K31K30K31K4CK50K46K41K4EK54K35K54K53K57K51K31K30K37K54K48K31K30K304) ANT switch and LPFThe RF amplifier output signal is passed through a low-pass filter network and a transmit/receive switching circuitbefore it is passed to the antenna terminal. The transmit/receive switching circuit is comprised of D101, D102 andD103. D102 and D103 turned on (conductive) in transmitmode and off (isolated) in receive mode.5) APCThe automatic power control (APC) circuit stabilizes thetransmitter output power at a predetermined level by sensingthe drain current of the final amplifier Field Effect Transistor(FET) . The voltage comparator, IC100 (2/2), compares thevoltage obtained from the above drain current with a referencevoltage which is set using the microprocessor. An APCvoltage proportional to the difference between the sensedvoltage and the reference voltage appears at the outp