TH-K2AT/K2E/K2ET DISASSEM BLY FOR REPAIR How to remove the case assembly from the chassis 1. Remove tw o screw s ( ) holding the chassis. 2. Pull out tw o knobs ( ) and remove tw o round nuts ( 3.
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TH-K2AT/K2E/K2ET DISASSEM BLY FOR REPAIR Soldering the antenna terminal 4. Apply the tips of soldering irons to all the four pins of the final FET at the same time ( ), heat them sufficiently, and remove 1. With the shield cover removed from the antenna terminal the final FET ( ).
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TH-K2AT/K2E/K2ET DISASSEM BLY FOR REPAIR Special care and attention required for assembly (2)By pressing the LCD hardw are fixture from the component side of the TX-RX PCB, you must bent all 4 tabs of the LCD 1. Gluing to the key top (M IC element section)
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TH-K2AT/K2E/K2ET DISASSEM BLY FOR REPAIR 4. Packing (G53-1572-02) TX/ BUSY lamp installation 6. Cautions for installing the chassis on the case assembly procedure (1)Verify that the packing (G53-1572-02) TX/BUSY lamp section (1)To assure w aterproofing, install the packing in the chassis is has been past through the hole in the illumination guide groove as show n in Fig.
TH-K2AT/K2E/K2ET CIRCUIT DESCRIPTION Frequency Configuration A tuning voltage corresponding to the desired signal is applied to each varicap through the BPF/APC terminal (pin 6) The frequency configuration is show n in Figure 1 and of the M PU (IC8) to tune to the receive frequency.
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TH-K2AT/K2E/K2ET CIRCUIT DESCRIPTION IF Circuit FM IC and band-pass filter consisting of R125, R126, R135, The first IF signal (38.85 MHz) amplified by the IF amplifier (Q24) C173, C174. The noise component is rectified in the FM IC to and the second IF signal (38.4 MHz) generated by tripling the 12.8...
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TH-K2AT/K2E/K2ET CIRCUIT DESCRIPTION Transmitter System The transmission/reception sw itching circuit consists of D10, L19, D12 and D13. These diodes are turned ON in transmit M icrophone Amplifier Circuit mode and OFF in receive mode to sw itch signals. The audio signal from the microphone passes through a high-pass filter (IC5) and enters a microphone amplifier (IC16).
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TH-K2AT/K2E/K2ET CIRCUIT DESCRIPTION The APC voltage controls the gate voltage of Q11 and Q12, amplifying VCO output w ith an RF amplifier (Q6) and dividing and keeps transmission output stable. it w ith the PLL IC. The M PU detects pow er supply voltage and controls Q58 The PLL synthesizer w ith 5 kHz and 6.25 kHz step is...
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TH-K2AT/K2E/K2ET CIRCUIT DESCRIPTION Pow er Supply Circuit Pow er Supply Sw itching Circuit The voltage supplied through the battery terminal or DC IN Charging Circuit terminal is branched in the pow er supply sw itching circuit as When an external pow er supply is connected to the DC IN show n in Fig.10 and then supplied to the required components.
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TH-K2AT/K2E/K2ET CIRCUIT DESCRIPTION Voltage Detection Circuit LED Drive Circuit Various voltages are input to the A/D port of the M PU (IC8) The LCD and key illumination LEDs are lighted by controlling for processing. Q51 for the LCD and Q50 for keys according to the output Battery voltage is divided w ith resistors (R240, R241) and voltage from the AF/LAM P AVR (Q37).
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TH-K2AT/K2E/K2ET CIRCUIT DESCRIPTION Key and Encoder Input Circuit The POWER key is assigned to the interrupt port (pin 95) of Other keys composes a matrix and key presses are detected the M PU. by scanning them by softw are. The PTT key is assigned to the dedicated port (pins 13, 14) The encoder reads data using the interrupt port (pins 35 of the M PU.
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TH-K2AT/K2E/K2ET CIRCUIT DESCRIPTION CTCSS/ DCS DTM F The encode signal is generated by the M PU (IC8) and output The DTM F signal is generated by the M PU (IC8) and is from the TONE terminal (pin 41) of the M PU.
TH-K2AT/K2E/K2ET SEM ICONDUCTOR DATA M PU : 90522BPFFG139 (IC8) Pin function Function Function Name Name Noise voltage input for squelch (A/D) CLOCK Common serial clock output RSSI voltage input for S-meter (A/D) DATA Common serial data output EEPDI Data input from EEPROM...
TH-K2AT/K2E/K2ET SEM ICONDUCTOR DATA / COM PONENTS DESCRIPTION COM PONENTS DESCRIPTION Function Name TX-RX UNIT (X57-674X-XX) DC IN detection interrupt input ( ↓ ) DCDET L:DC IN connected Ref. No. Use/Function Operation/Condition/Compatibility RXLED Busy LED output H:ON PLL IC 100 BSFT...
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TH-K2AT/K2E/K2ET COM PONENTS DESCRIPTION Ref. No. Use/Function Operation/Condition/Compatibility Ref. No. Use/Function Operation/Condition/Compatibility Q33 operation Reverse current On w hen charging Battery sw itch prevention DC IN detection H: DC IN detection Ni-MH temperature On w hen temperature detection is constant-voltage...
E,E3 TX-RX UNIT (X54-674X-XX) B62-1758-00 INSTRUCTION M ANUAL(DUTCH) E,E3 0-11 : K, K2 0-21 : M, M2 2-71 : E 2-72 : E3 B72-2128-04 M ODEL NAM E PLATE(TH-K2AT) K,K2,M B72-2128-04 M ODEL NAM E PLATE(TH-K2AT) B30-2156-05 LED(RED) B30-2157-05 LED(YELLOW )
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CK73HB1H102K CHIP C 1000PF K C227 C92-0587-05 CHIP-TAN 2.2UF 4W V C135 CC73HCH1H120J CHIP C 12PF C228,229 CK73HB1A104K CHIP C 0.10UF K E : TH-K2E K : TH-K2AT M : TH-K2AT E3 : TH-K2ET K2 : TH-K2AT M2 : TH-K2AT...
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C357 CK73EF1C105Z CHIP C 1.0UF L40-1575-71 SM ALL FIXED INDUCTOR(15NH) ∗ C358 CK73HB1A473K CHIP C 0.047UF K L40-5675-71 SM ALL FIXED INDUCTOR(56NH) E : TH-K2E K : TH-K2AT M : TH-K2AT E3 : TH-K2ET K2 : TH-K2AT M2 : TH-K2AT...
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J 1/ 16W R157,158 RK73HB1J334J CHIP R 330K J 1/ 16W R92-1368-05 CHIP R 0 OHM R159 RK73HB1J124J CHIP R 120K J 1/ 16W E : TH-K2E K : TH-K2AT M : TH-K2AT E3 : TH-K2ET K2 : TH-K2AT M2 : TH-K2AT...
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RK73HB1J221J CHIP R J 1/ 16W K,K2,M ∗ R230 RK73HB1J221J CHIP R J 1/ 16W M 2,E3 S70-0485-05 TACT SW ITCH (PTT) E : TH-K2E K : TH-K2AT M : TH-K2AT E3 : TH-K2ET K2 : TH-K2AT M2 : TH-K2AT...
TH-K2AT/K2E/K2ET EXPLODED VIEW (TH-K2AT / K2ET) TX-RX Unit (B/3) TX-RX Unit (C/3) TX-RX Unit (A/3) 702. STANDARD LABEL : K, K2 701. STICKER A : N09-1492-05 B : N14-0569-04 C : N14-0573-04 D : N79-2035-46 1 (K2, M 2) E : N79-2040-45...
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TH-K2AT/K2E/K2ET EXPLODED VIEW (TH-K2E) TX-RX Unit (B/3) TX-RX Unit (C/3) TX-RX Unit (A/3) 701. STICKER A : N09-1492-05 B : N14-0569-04 C : N14-0573-04 D : N79-2035-46 E : N79-2040-45 F : N82-2007-46 G : N09-2433-05 Parts with the exploded numbers larger than 700 are not supplied.
TH-K2AT/K2E/K2ET ADJUSTM ENT Single Tone M ode G. 7.5V TX M pow er (Low er limit frequency, center frequency, upper limit frequency) This mode is used to check the DTM F deviation. H. 7.5V TX L pow er (Low er limit frequency, center frequency,...
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TH-K2AT/K2E/K2ET ADJUSTM ENT [F] key → [key] Key name [key] Transmit w hile this key is held dow n. Selecting a TX pow er (High/M id/Low ) Changes adjustment items. (Forw ard) LAM P Lamp alw ays ON When this key is pressed on the frequency display, it sw itches to the adjustment display.
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TH-K2AT/K2E/K2ET ADJUSTM ENT D. S-meter (Tw o segments in S-meter light, all segments 2 RX BPF (Center frequency) in S-meter light) (1)Press the [LAM P] or [M ONI] key on the transceiver to display 1 S-meter (Tw o segments in S-meter light) “...
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TH-K2AT/K2E/K2ET ADJUSTM ENT (8) Press the [M ENU] key to w rite the current APC value into (5) Press the [PTT] key to enable the transmit mode. the EEPROM . (6) Adjust the output voltage from DC pow er supply until the voltage at the battery terminal becomes 7.5V w hile the...
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TH-K2AT/K2E/K2ET ADJUSTM ENT (2)Press the [VFO], [M R] or [CALL] key to sw itch to the The current APC value is displayed at the low er digits of frequency display. the frequency display, and the value stored in the EEPROM (3)Turn the encoder to display the low er limit frequency on is displayed on the memory channel number display.
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TH-K2AT/K2E/K2ET ADJUSTM ENT J. 13.8V TX M pow er (Low er limit frequency, center (4) Repeat steps (4) to (7) of “ 1 13.8V TX M pow er (Low er frequency, upper limit frequency) limit frequency)” described on page 32.
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TH-K2AT/K2E/K2ET ADJUSTM ENT 2 Tone deviation (Center frequency) (2)Press the [VFO], [M R] or [CALL] key to sw itch to the frequency display. (1)Press the [LAM P] or [M ONI] key on the transceiver to display (3)Turn the encoder to display the upper limit frequency on “...
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TH-K2AT/K2E/K2ET ADJUSTM ENT (4) Press the [CALL] key to sw itch to the adjustment display. (2) Input a specified AG signal to microphone input. (5) When the [PTT] key is pressed to enable transmit mode, a (3) Press the [M ENU] key to w rite the current microphone input preset DCS code (023) is int ernally generat ed and level value into the EEPROM .
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TH-K2AT/K2E/K2ET ADJUSTM ENT Common Section M easurement Adjustment Specifications/ Item Condition Remarks Test equipment Unit Terminal Unit Parts M ethod 1.Setting and Connect the optional PG-2W LCD total illumination display Initial configuration displayed after resetting DC cable to the pow er supply.
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TH-K2AT/K2E/K2ET ADJUSTM ENT Receiver section M easurement Adjustment Specifications/ Item Condition Remarks Test equipment Unit Terminal Unit Parts M ethod 1.RX BPF Squelch level: 0 Adjust 1) Frequency: 145.050M Hz TX-RX Turn the VOL knob 0.63V (E, E3) Oscilloscope (A/3) knob to obtain 0.63V AF...
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TH-K2AT/K2E/K2ET ADJUSTM ENT M easurement Adjustment Specifications/ Item Condition Remarks Test equipment Unit Terminal Unit Parts M ethod Sw itch to Adjustment mode and carry out the operations for adjustment item D. (Refer to page 29) S-meter 3) LCD display: S1...
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TH-K2AT/K2E/K2ET ADJUSTM ENT M easurement Adjustment Specifications/ Item Condition Remarks Test equipment Unit Terminal Unit Parts M ethod 8.AF output 1) Frequency: 145.050M Hz TX-RX Check 400mW or more Check (E, E3) Oscilloscope (A/3) Frequency: 146.050M Hz Distortion meter (K, K2, M , M 2) AF V.M SSG output: –53dBm (501uV)
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TH-K2AT/K2E/K2ET ADJUSTM ENT M easurement Adjustment Specifications/ Item Condition Remarks Test equipment Unit Terminal Unit Parts M ethod 6) LCD display: P7H, Pow er meter TX-RX Encoder Write M id pow er Frequency: 145.995M Hz Am meter (A/3) [M ENU]...
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TH-K2AT/K2E/K2ET ADJUSTM ENT M easurement Adjustment Specifications/ Item Condition Remarks Test equipment Unit Terminal Unit Parts M ethod 8) LCD display: P13C, Pow er meter TX-RX Encoder Write 0.5W ±0.05W Frequency: 145.000M Hz Am meter (A/3) [M ENU] 0.8A or less...
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TH-K2AT/K2E/K2ET ADJUSTM ENT M easurement Adjustment Specifications/ Item Condition Remarks Test equipment Unit Terminal Unit Parts M ethod 1)Frequency: 145.000M Hz Linear detector TX-RX 4.2kHz ±0.1kHz (E, E3) (A/3) M IC According to the Frequency: 146.000M Hz Oscilloscope larger +, –.
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TH-K2AT/K2E/K2ET ADJUSTM ENT M easurement Adjustment Specifications/ Item Condition Remarks Test equipment Unit Terminal Unit Parts M ethod 9.VOX Sw itch to Adjustment mode TX-RX M IC Sensitivity and carry out the operations (A/3) Write for adjustment item O. (Refer to page 34)
TH-K2AT/K2E/K2ET ADJUSTM ENT / TERM INAL FUNCTION Adjustment points TERM INAL FUNCTION TX-RX unit (A/ 3) CN No. Pin No. Pin Name Function Component side view TX-RX UNIT (A/ 3) : TX-RX↔VOL/ ENC Vol-OUT RX audio volume output Vol-IN RX audio volume input...
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TH-K2AT/K2E/K2ET PC BOARD TX-RX UNIT (X57-674X-XX) (A/ 3) Component side view (J72-0883-09 A/ 3) 0-11 : K,K2 0-21 : M ,M 2 2-71 : E 2-72 : E3 R252 R231 C128 R144 R143 C126 C271 R137 R131 R149 R151 R152...
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TH-K2AT/K2E/K2ET PC BOARD TX-RX UNIT (X57-674X-XX) (A/ 3) Component side view (J72-0883-09 A/ 3) 0-11 : K,K2 0-21 : M ,M 2 2-71 : E 2-72 : E3 C310 POWER COM 0 R246 R248 COM 1 COM 2 COM 3...
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TH-K2AT/K2E/K2ET PC BOARD TX-RX UNIT (X57-674X-XX) (A/ 3) Foil side view (J72-0883-09 A/ 3) 0-11 : K,K2 0-21 : M ,M 2 2-71 : E 2-72 : E3 C100 C162 C160 R111 C158 R291 R110 R102 R345 C502 C159 CN15...
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TH-K2AT/K2E/K2ET PC BOARD TX-RX UNIT (X57-674X-XX) (A/ 3) Foil side view (J72-0883-09 A/ 3) 0-11 : K,K2 0-21 : M ,M 2 2-71 : E 2-72 : E3 R100 C145 C500 C501 C136 R102 C137 R341 R347 C325 C134 R346...
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TH-K2AT/K2E/K2ET TH-K2AT/K2E/K2ET PC BOARD PC BOARD TX-RX UNIT (X57-674X-XX) (A/ 3) Component side view (J72-0883-09 A/ 3) TX-RX UNIT (X57-674X-XX) (A/ 3) Component side view (J72-0883-09 A/ 3) 0-11 : K,K2 0-21 : M ,M 2 2-71 : E 2-72 : E3...
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TH-K2AT/K2E/K2ET TH-K2AT/K2E/K2ET PC BOARD PC BOARD TX-RX UNIT (X57-674X-XX) (A/ 3) Foil side view (J72-0883-09 A/ 3) TX-RX UNIT (X57-674X-XX) (A/ 3) Foil side view (J72-0883-09 A/ 3) 0-11 : K,K2 0-21 : M ,M 2 2-71 : E 2-72 : E3...
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TH-K2AT/K2E/K2ET PC BOARD TX-RX UNIT (X57-674X-XX) (B,C/ 3) Component side view (J72-0883-09 B,C/ 3) 0-11 : K,K2 0-21 : M ,M 2 2-71 : E 2-72 : E3 M IC1 M ENU – 2/VFO 3/M R F/CALL CALL J72-0883-09 (B/3)
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TH-K2AT/K2E/K2ET PC BOARD TX-RX UNIT (X57-674X-XX) (B,C/ 3) Foil side view (J72-0883-09 B,C/ 3) 0-11 : K,K2 0-21 : M ,M 2 2-71 : E 2-72 : E3 C243 KIN3 KYO2 KIN0 KYO1 KIN2 KYO0 – LAMP M IG KIN4...
TH-K2AT/K2E/K2ET BT-14 (BATTERY CASE) / PG-4Y (PROGRAM M ING INTERFACE CABLE) / M CP-1A (M EM ORY CONTROL PROGRAM ) BT-14 (6 AA/ LR6) External View PG-4Y External View M CP-1A • Available free for dow nloading from the Kenw ood w ebsite:...
Sales M arketing Division KENWOOD ELECTRONICS U.K. LIM ITED 1 Ang M o Kio Street 63, Singapore 569110 KENWOOD House, Dw ight Road, Watford, Herts., WD18 9EB, United Kingdom KENWOOD ELECTRONICS EUROPE B.V. Amsterdamsew eg 37, 1422 AC Uithoorn, The Netherlands...