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Kenwood. Disclaimer While every precaution has been taken in the preparation of this manual, Kenwood assumes no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein. Kenwood reserves...
X57-6190-21 240~270MHz SYSTEM SET-UP Merchandise received Frequency range (MHz) RF power Type TX 218~250 5.0W TK-285 K,E RX 217~250 Choose the type of transceiver TX/RX 240~270 5.0W TK-285 (N)M Transceiver programming A personal computer (IBM PC or compatible), programming interface (KPG-36), and programming software (KPG-62D) are required for programming.
OPERATING FEATURES 2-3. Key functions 1. Operation Features Trunking mode The TK-285 is a VHF FM Radio designed in both Trunking 2 Rotary encoder Mode and Conventional Mode. Rotate this encoder to select your desired call address (voice calls) ot status (status calls).
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5-2. Connection procedure 1. Connect the TK-285 to the personal computer with the interface cable. 2. When the POWER switch on, user mode can be entered REALIGNMENT immediately.
3. Set the firmware to be updated by File name item. The KPG-36 connects the universal connector of the TK- 4. Turn the TK-285 power ON with the [A] switch held down. 285 to the computers RS-232C serial port. Hold the switch down until the display changes to "PROG 57600".
TK-285/(N) CIRCUIT DESCRIPTION 1. Overview 3. Receiver System This transceiver is VHF/FM portable transceiver designed 3-1. RF unit to operate in the frequency range of 217 to 250MHz (K, E), An incoming RF signal from the antenna terminal is passed 240 to 270MHz ((N)M).
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TK-285/(N) CIRCUIT DESCRIPTION 3-3. Audio amplifier circuit 3-4. Squelch circuit The demodulated signal from IC12 goes through the mute The output from IC12 enters FM IC again, then passed switch (Q15) and is amplified by IC4 (2/2), high-pass filtered, through a band-pass filter. The noise component output from...
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EXT. is applied to pin 8 of the PLL IC. IC13 Q300 IC25(1/2) The TK-285’s VCO consists of 2VCO and covers a dual COMP LIMIT range of the 261.85~294.85MHz (K,E), 284.85~314.85MHz ((N)M) and the 218~250MHz (K,E), 240~270MHz ((N)M). IC7 (1/2)
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TK-285/(N) CIRCUIT DESCRIPTION 6-2. Low battery warning 6. Control Circuit The battery voltage is monitored by the microprocessor The control circuit consists of microprocessor (IC19) and (IC19). When the battery voltage falls below the voltage set by its peripheral circuits. It controls the TX-RX unit and transfers the Low Battery Warning adjustment, the red LED flashes to data to and from the display unit.
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TK-285/(N) CIRCUIT DESCRIPTION 7-2. Decode 7. Signalling Circuit Low-speed data (QT,DQT) 7-1. Encode The demodulated signal from the IF IC (IC12) is amplified Low-speed data (QT,DQT) by IC4 (2/2) and passes through a low-pass filter (IC11) to Low-speed data is output from pin 1 of the CPU. The signal remove audio components.
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TK-285/(N) CIRCUIT DESCRIPTION / SEMICONDUCTOR DATA 9. Optional Board Terminal SEMICONDUCTOR DATA Terminals for mounting the option board are provided at Microprocesser : 30620M8-394GP the bottom edge of the TX-RX unit. The table below shows the (TX-RX UNIT : IC19) correspondence between the board and terminals.
TK-285/(N) DESCRIPTION OF COMPONENTS DISPLAY UNIT (X54-3210-13) Ref. No. Use/Function Operation/Condition Ref. No. Use/Function Operation/Condition IC300 Audio power amplifier Transistor IF W/N switch sets to on when Wide IC301 Counter /Key scan Transistor Ripple filter Q300 DC switch / INT MIC on/off...
TK-285/(N) PARTS LIST L: Scandinavia K: USA P: Canada ∗ New Parts. indicates safety critical components. Y: PX (Far East, Hawaii) T: England E: Europe Parts without Parts No. are not supplied. Y: AAFES (Europe) X: Australia M: Other Areas Les articles non mentionnes dans le Parts No.
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TK-285/(N) PARTS LIST DISPLAY UNIT (X54-3210-13) TX-RX UNIT (X57-619X-XX) TX-RX UNIT (X57-619X-XX) Ref. No. Address Parts No. Description Destination Ref. No. Address Parts No. Description Destination parts parts Q309 2SC4617(S) TRANSISTOR L300,301 L92-0141-05 FERRITE CHIP L302,303 L92-0138-05 FERRITE CHIP Q310...
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TK-285/(N) PARTS LIST TX-RX UNIT (X57-619X-XX) Ref. No. Address Parts No. Description Destination Ref. No. Address Parts No. Description Destination parts parts C64,65 CC73GCH1H680J CHIP C 68PF C132 CC73GCH1H220J CHIP C 22PF CK73GB1C104K CHIP C 0.10UF C133 CK73GB1E153K CHIP C 0.015UF K...
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TK-285/(N) PARTS LIST TX-RX UNIT (X57-619X-XX) Ref. No. Address Parts No. Description Destination Ref. No. Address Parts No. Description Destination parts parts C204 CC73GCH1H330J CHIP C 33PF C256,257 CK73HB1C103K CHIP C 0.010UF K C205 CK73GB1H102K CHIP C 1000PF C259 CK73GB1E103K CHIP C 0.010UF K...
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TK-285/(N) PARTS LIST TX-RX UNIT (X57-619X-XX) Ref. No. Address Parts No. Description Destination Ref. No. Address Parts No. Description Destination parts parts L92-0138-05 FERRITE CHIP RK73GB1J473J CHIP R J 1/16W L40-3978-67 SMALL FIXED INDUCTOR(39NH) (N)M RK73GB1J472J CHIP R 4.7K J 1/16W...
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TK-285/(N) PARTS LIST TX-RX UNIT (X57-619X-XX) Ref. No. Address Parts No. Description Destination Ref. No. Address Parts No. Description Destination parts parts RK73GB1J103J CHIP R J 1/16W R218 RK73GB1J220J CHIP R J 1/16W RK73GB1J183J CHIP R J 1/16W R219 RK73GB1J470J...
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TK-285/(N) PARTS LIST TX-RX UNIT (X57-619X-XX) SUB UNIT (X58-4730-XX) TX-RX UNIT (X57-619X-XX) Ref. No. Address Parts No. Description Destination Ref. No. Address Parts No. Description Destination parts parts R415,416 RK73GB1J474J CHIP R 470K J 1/16W 2SK1824 2SC5108(Y) TRANSISTOR 1SR154-400 DIODE...
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TK-285/(N) PARTS LIST TX-RX UNIT (X57-619X-XX) SUB UNIT (X58-4730-XX) Ref. No. Address Parts No. Description Destination Ref. No. Address Parts No. Description Destination parts parts RK73HB1J104J CHIP R 100K J 1/16W R5,6 RK73HB1J391J CHIP R J 1/16W RK73HB1J334J CHIP R...
TK-285/(N) EXPLODED VIEW Display unit (A/2) A NUT :N14-0569-04 B M2.6x4 :N30-2604-46 C M2.6x10 :N30-2610-46 D M2.6x6 :N67-2606-46 :N79-2025-46 F M2x5 :N83-2005-46 IC100 Sub unit TX-RX unit 24 61 Display unit (B/2) (CHASSIS) S/NO label (ESN) S/NO label Parts with the exploded numbers larger than 700 are not supplied.
TK-285/(N) PACKING 62 Battery assy (W09-0900-35) E type only Warranty card K type only 43 Carton board (H13-1072-04) K,(N)M type only 7 Instrution manual (B62-1264-00) 57 Screw set (N99-2004-05) 3 Cap (B09-0363-03) 42 Packing fixture (H12-3014-02) ANT Helical antenna (T90-0733-05):K,E...
TK-285/(N) ADJUSTMENT Test Equipment Required for Alignment Test Equipment Major Specifications Standard Signal Generator Frequency Range 217 to 270MHz (SSG) Modulation Frequency modulation and external modulation. Output -127dBm/0.1µV to greater than -47dBm/1mV Power Meter Input Impedance 50Ω. Operation Frequency 217 to 270MHz or more.
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ADJUSTMENT • Panel tuning Repair Jig (Chassis) Use jig (part No.: W05-0825-00) for repairing the TK-285. The jig facilitates the voltage check and protects the module when the voltage on the flow side of the TX-RX unit is checked 2: RED (RX AF OUTPUT) during repairs.
TK-285/(N) ADJUSTMENT Frequency and signalling Test Mode The set has been adjusted for the frequencies shown in the Test mode operating features following table. When required. re-adjust them following the This transceiver has a test mode. To enter test mode, press adjustment procedure to obtain the frequencies you want in [B] key and turn power on.
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TK-285/(N) ADJUSTMENT • Transceiver tuning LCD display (Tuning mode) (To place transceiver in tuning mode) FREQ Channel appears on LCD. Set channel according to tuning requirements. Adjustment item Adjustment (1~256) LCD display (Test mode) Panel Tuning Mode (K, E type)
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TK-285/(N) ADJUSTMENT Common Section Measurement Adjustment Specifications/ Item Condition Remark Test equipment Unit Terminal Unit Parts Method 1. Setting 1) BATT terminal voltage:7.5V 2) SSG Standard modulation MOD:1kHz, DEV:1.5kHz 2. VCO lock [Panel Test Mode] voltage 1) CH-Sig:2-1 Power meter...
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TK-285/(N) ADJUSTMENT Transmitter Section [Panel Tuning Mode except when Panel TEST Mode is specified.] Measurement Adjustment Specifications/ Item Condition Remark Test equipment Unit Terminal Unit Parts Method 7. DQT Balance 1) Adj item [BAL] Power meter Panel Panel Encoder Make the Adjust Adjust [∗∗∗]...
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TK-285/(N) ADJUSTMENT Transmitter Section [Panel Tuning Mode except when Panel TEST Mode is specified.] Measurement Adjustment Specifications/ Item Condition Remark Test equipment Unit Terminal Unit Parts Method ±0.05kHz 14.TONE 1) Adj item [TONE] Power meter Panel Panel Encoder 1.45kHz Deviation Adjust [∗∗∗]...
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TK-285/(N) ADJUSTMENT Receiver Section [Panel Tuning Mode except when Panel TEST Mode is specified.] Measurement Adjustment Specifications/ Item Condition Remark Test equipment Unit Terminal Unit Parts Method 4. RSSI 1) Adj item [LRSI] Panel Panel Encoder After input (Low) Adjust [∗∗∗]...
TK-285/(N) TERMINAL FUNCTION CN No. Pin No. Name I/O Function CN No. Pin No. Name I/O Function TX-RX UNIT (X57-619X-XX): TX-RX section PTT signal output. Not use. Power input after passing through LCD driver chip select input. the fuse. Audio mute signal input.