Kenwood TM-481A Service Manual Download

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Q903

Q904

R901

R909

R916

R917

R919

CN901

C903

C910

VR901

CALL

VFO

HOOK

GND

MBL

MIC

PTT

HOOK

GND

MBL

MIC

PTT

J901

D904

D906

D907

D908

D909

Q901

Q902

R914

R915

R918

R920

R921

R922

R923

R924

C901

C902

C912

C915

C916

C917

C918

C929

D901

D902

SPGND

SPOUT

RXD

PTT

VOL

MICKEY

ENCA

ENCB

BRI

POWER

MIC

GND

TX-RX UNIT (X57-

130-24) (B/2): DISPLAY SECTION

Component side view (J79-0316-19 B/2)

TX-RX UNIT (X57-

130-24) (B/2): DISPLAY SECTION

Foil side view (J79-0316-19 B/2)

PC BOARD

TM-481A

Summary of Contents for TM-481A

Page 1: ...29 9497 01 Modular jack MIC E58 0535 05 Panel assy A62 1189 03 Knob VOL K29 9498 03 Knob ENC K29 9499 03 4 DISASSEMBLY FOR REPAIR 2 CIRCUIT DESCRIPTION 5 COMPONENTS DESCRIPTION 9 SEMICONDUCTOR DATA 11 PARTS LIST 12 EXPLODED VIEW 18 PACKING 19 ADJUSTMENT 20 TERMINAL FUNCTION 29 PC BOARD TX RX UNIT X57 8130 24 30 SCHEMATIC DIAGRAM 36 BLOCK DIAGRAM 40 LEVEL DIAGRAM 42 SPECIFICATIONS BACK COVER CONTEN...

Page 2: ...med for damages resulting from the use of the informa tion contained herein JVC KENWOOD Corporation reserves the right to make changes to any products herein at any time for improvement purposes 1 Disassembly Procedure 1 When removing the cabinet first remove the two screws from the right and left with a phillips screwdriver Then hook your finger on the edge of the cabinet and pull it out until it...

Page 3: ... the key top Panel assembly Display PCB Ĭ ĭ Į Į į İ 5 When removing the TX RX PCB first remove the solder of the antenna hot pin and positive terminal of the DC cord Then remove the 15 screws from the TX RX PCB power module and audio amp Positive terminal of the DC cord Antenna hot pin Power module TX RX PCB Audio amp Note When you supply power to the TX RX PCB after removing the TX RX PCB from th...

Page 4: ...me knob Key top Panel assembly Display PCB Speaker Ĭ Ĭ ĭ Į į 2 When mounting the panel assembly pass the flat cable through the hole of the chassis as shown below then con nect the flat cable to connector of the panel assembly Hole of the chassis Panel assembly Panel assembly Chassis Chassis 3 Fit the panel assembly into the two tabs of the chassis top side first Then fit the panel assembly into t...

Page 5: ...ithic crystal filter MCF XF501 to further remove spurious signals IF Amplifier The first IF signal is amplified by Q503 and then goes to IC501 FM processing IC The signal is heterodyned again with a second local oscillator signal within IC501 to create a 450kHz second IF signal The second IF signal is then fed through a 450kHz ceramic filter Wide CF501 Narrow CF502 to further eliminate unwanted si...

Page 6: ... electric field strength of the receive signal can be known be fore the SQIN voltage is input to the MCU and the scan stop speed is improved Q502 NOISE AMP D503 IC501 IC707 FILOUT RSSI DET MCU FM IC SQIN RSSI Fig 5 Squelch circuit PLL Frequency Synthesizer The PLL circuit generates the first local oscillator signal for reception and the RF signal for transmission PLL The frequency step of the PLL ...

Page 7: ...he power module IC302 through a low pass filter The low pass filter removes unwanted high frequency harmonic components and the resulting signal is transmitted through the antenna terminal See Fig 8 APC Circuit The automatic transmission power control APC circuit detects part of a final amplifier output with a diode D313 D314 and applies a voltage to IC303 IC303 compares the APC control voltage PC...

Page 8: ...s Each of them is con nected to a cross point of a matrix of the KI1 to KI3 and KSI to KS2 ports of the LCD driver The LCD driver monitors the status of the KI1 to KI3 and KS1 to KS2 ports If the state of one of the ports changes the LCD driver assumes that the key at the matrix point cor responding to that port has been pressed IC901 LCD driver KI1 KI2 KI3 KS2 KS1 FUNC REV CALL VFO MR MHz Encoder...

Page 9: ...r stop mode This circuit has an overvoltage protection circuit If a DC voltage of 18V or higher is applied to the base of Q707 this voltage turns Q707 on and will set to high on MCU port 18 INT The MCU will then send the backup data to the EE PROM IC708 and enter stop mode See Fig 16 Q714 SW Q713 SW Q707 SW IC713 AVR D712 D710 B IC714 RST SBC R824 R825 INT 5M IC707 MCU POWER SW POWER RESET 5M IC71...

Page 10: ...ch Q902 DC switch Q903 LCD backlight switch Q904 Brightness function switch D1 Voltage dropped D2 Ripple filter D3 VCO frequency control RX D4 VCO frequency control TX Ref No Use Function Operation Condition Compatibility D5 VCO frequency control RX D6 VCO frequency control TX D7 VCO modulation D8 Ripple filter D9 10 RF switch TX RX D301 Voltage protection 5 1V Zener diode D305 Protection PC TV D3...

Page 11: ...Not used 45 49 NC I Not used 50 AFM O AF mute 51 SPM O Speaker mute 52 AMPSW O AF AMP switch Pin No Name I O Function 53 DT O Common data 54 CK O Common clock 55 NC I Not used 56 DST1 I Destination 1 57 59 DST2 DST4 I Destination 2 4 60 VCC 5V 61 NC I Not used 62 VSS GND 63 ADJ I For adjustment mode 64 NARROW O Narrow 65 WIDE O Wide 66 67 NC I Not used 68 CL O Clock for LCD 69 CE O Chip enable for...

Page 12: ...3HCH1H101J CHIP C 100PF J C347 CK73HB1E104K CHIP C 0 10UF K C348 CK73HB1H471K CHIP C 470PF K C350 CK73HB1H102K CHIP C 1000PF K C354 CC73HCH1H220J CHIP C 22PF J C355 CC73HCH1H470J CHIP C 47PF J C356 CC73HCH1H220J CHIP C 22PF J C394 CK73HB1E104K CHIP C 0 10UF K C395 CK73HB1H471K CHIP C 470PF K C397 CK73HB1H471K CHIP C 470PF K C399 CK73HB1H103K CHIP C 0 010UF K C400 401 CK73HB1H471K CHIP C 470PF K C4...

Page 13: ...CHIP C 24PF J C555 CC73HCH1H010B CHIP C 1 0PF B C556 CK73HB1H471K CHIP C 470PF K C557 CC73HCH1H0R5B CHIP C 0 5PF B C558 CC73HCH1H150J CHIP C 15PF J C559 CK73HB1H471K CHIP C 470PF K C560 CC73HCH1H010B CHIP C 1 0PF B C561 562 CK73HB1H471K CHIP C 470PF K C563 CC73HCH1H010B CHIP C 1 0PF B C564 CC73HCH1H300J CHIP C 30PF J C565 569 CK73HB1H471K CHIP C 470PF K C570 CC73HCH1H0R3B CHIP C 0 3PF B C571 CC73H...

Page 14: ... CC73HCH1H470J CHIP C 47PF J C901 903 CK73HB1A104K CHIP C 0 10UF K C910 CK73HB1H102K CHIP C 1000PF K C912 CK73HB1H102K CHIP C 1000PF K C915 CC73HCH1H101J CHIP C 100PF J C916 918 CK73HB1H102K CHIP C 1000PF K C920 CK73HB1H471K CHIP C 470PF K C921 CK73GB1A105K CHIP C 1 0UF K C922 CK73HB1H102K CHIP C 1000PF K C924 CK73HB1A104K CHIP C 0 10UF K C926 927 CC73HCH1H101J CHIP C 100PF J C928 CK73HB1H681K CHI...

Page 15: ... 1 16W R349 RK73EB2E221J CHIP R 220 J 1 4W R350 RK73GB2A100J CHIP R 10 J 1 10W R351 RK73HB1J473J CHIP R 47K J 1 16W R377 378 RK73HB1J103J CHIP R 10K J 1 16W R380 2B R92 1061 05 JUMPER REST 0 OHM R381 R92 1061 05 JUMPER REST 0 OHM R501 RK73HB1J124J CHIP R 120K J 1 16W R502 RK73HB1J101J CHIP R 100 J 1 16W R503 RK73HB1J223J CHIP R 22K J 1 16W R504 507 RK73HB1J103J CHIP R 10K J 1 16W R508 RK73HB1J223J...

Page 16: ...789 RK73HB1J224J CHIP R 220K J 1 16W R790 RK73HB1J123J CHIP R 12K J 1 16W R791 RK73GH2A124D CHIP R 120K D 1 10W R792 RK73GH2A562D CHIP R 5 6K D 1 10W R793 RK73GH2A913D CHIP R 91K D 1 10W R794 RK73HB1J124J CHIP R 120K J 1 16W R795 RK73GH2A562D CHIP R 5 6K D 1 10W R796 RK73HB1J183J CHIP R 18K J 1 16W R797 RK73HB1J272J CHIP R 2 7K J 1 16W R799 RK73HB1J474J CHIP R 470K J 1 16W R800 RK73HB1J562J CHIP R...

Page 17: ...00V ZB MOS IC IC704 NJM12904RB1 MOS IC IC705 M62363FP F MOS IC IC706 BA10324AFV MOS IC IC707 30622MEP594GU MICROCONTROLLER IC IC708 EX24064ASAS0A ROM IC IC709 BA10324AFV MOS IC IC710 XC6209B502P G MOS IC IC711 TA7808F NQ ANALOGUE IC IC712 XC61CN4002MR MOS IC IC713 TA7805F NQ MOS IC IC714 XC61CN3202MR MOS IC IC715 1A LA4600 BI POLAR IC IC901 PT6554LQ MOS IC Q1 2SA1832 GR F TRANSISTOR Q2 2SC4738 GR ...

Page 18: ...w of the PCB that part does not come with the PCB These parts must be ordered separately B A 3 2 1 1 10 2 11 13 15 IC302 R380 IC715 J701 B B B B D Dx2 Dx4 X57 A 2 X57 A 2 TX RX unit B 2 Display section TX RX unit A 2 TX RX section Dx2 D D D D A A 700 702 703 A N35 2604 43 B N67 3008 48 C N80 2008 48 D N87 2608 48 3 5 6 12 19 19 16 20 27 30 31 32 36 C C 18 ...

Page 19: ...Microphone T91 0641 75 14 DC cord E30 7744 05 17 Fuse Blade type 15A F52 0024 05 26 Holder MIC J19 1584 15 34 Screw set N99 2082 05 28 Bracket J29 0726 03 713 Protection bag 715 Packing fixture 716 Packing fixture 717 Item carton case 710 Protection bag 7 Instruction manual 711 Pamphlet B62 2348 10 ...

Page 20: ...analyzer Measuring range 10kHz to 1GHz or more 10 Oscilloscope High sensitivity with horizontal input terminal 11 Standard signal generator SSG Frequency range 400 to 470MHz Output 133dBm 0 05µV to greater than 13dBm 50mV 12 Dummy load for AF 8 about 5W 13 Sweep generator The sweep generator must be able to sweep the frequen cy range of 30 to 600MHz 14 Tracking generator Output voltage 100mV or mo...

Page 21: ...adjustment mode Panel Key Operation Method in Adjustment Mode Ĭ ĭ Į į İ ı Ĳ Power switch Volume control When the Tuning control is pressed once the adjustment value display blinks Select an adjustment item with the VFO or MR key before performing the operation It cannot be performed while transmitting When the Tuning control is rotated while the adjustment display is blinking the adjustment value ...

Page 22: ...050 CTCSS 88 5Hz Center 435 100 435 050 High 469 900 469 950 9 CTCSS Fine Deviation Narrow Center CT and N icon appear 435 100 435 050 10 DCS Fine Deviation Low DCS icon appear 400 100 400 050 DCS 023N Center 435 100 435 050 High 469 900 469 950 11 DCS Fine Deviation Narrow Center DCS and N icons appear 435 100 435 050 12 DTMF Fine Deviation Center 435 100 435 050 DTMF 9 13 DTMF Fine Deviation Nar...

Page 23: ... 401 pts VBW 100 kHz W1 S2 S3 FC AA Center 400 1 MHz Res BW 100 kHz Source Amptd 30 00 dBm 1 Fig 1 Ref 20 dBm Peak Log 10 dB Atten 5 dB Mkr1 435 1 MHz 58 81 dBm Span 200 MHz Sweep 50 ms 401 pts VBW 100 kHz W1 S2 S3 FC AA Center 435 1 MHz Res BW 100 kHz Source Amptd 30 00 dBm 1 Fig 2 Ref 20 dBm Peak Log 10 dB Atten 5 dB Mkr1 470 0 MHz 60 55 dBm Span 200 MHz Sweep 50 ms 401 pts VBW 100 kHz W1 S2 S3 ...

Page 24: ...rogram before performing the full reset then write the data to the transceiver after performing the adjust ment Confirm that all LCD segments light 3 VCO Lock voltage RX 1 Frequency 469 950MHz DVM TX RX A 2 CV TX RX A 2 TC2 5 5V 0 1V 2 Frequency 400 050MHz Check 0 5V or more TX 3 Frequency 469 900MHz 4 Transmit TX RX A 2 TC1 5 5V 0 1V 5 Frequency 400 100MHz 6 Transmit Check 0 5V or more Transmitte...

Page 25: ... 2 Transmit Linear detector Oscilloscope By turning the Tun ing control adjust the modulation wave until it becomes the square wave Center 3 Adj item BALC Adjust ᲤᲤ 4 Transmit High 5 Adj item BALH Adjust ᲤᲤ 6 Transmit Narrow Center 7 Adj item BALC N icon appear Adjust ᲤᲤ 8 Transmit 5 MAX deviation Wide Low 1 Adj item MAXL Adjust ᲤᲤ AG 1kHz 54mV Detector P P LPF 15kHz HPF OFF De emphasis OFF 2 Tran...

Page 26: ...75kHz 0 05kHz Center 3 Adj item DVC CT icon appear Adjust ᲤᲤ 4 Transmit High 5 Adj item DVH CT icon appear Adjust ᲤᲤ 6 Transmit Narrow Center 7 Adj item DVC CT and N icon appear Adjust ᲤᲤ 8 Transmit 0 37kHz 0 05kHz 8 DCS fine deviation Wide Low 1 Adj item DVL DCS icon appear Detector P P 2 LPF 3kHz HPF OFF De emphasis OFF 2 Transmit 0 75kHz 0 05kHz Center 3 Adj item DVC DCS icon appear Adjust ᲤᲤ 4...

Page 27: ...n Refer to Fig 1 page 23 Center 4 Adj item BPC Adjust ᲤᲤ 5 Spectrum analyzer setting Center f 435 050MHz Span 200MHz RBW 100kHz VBW 100kHz ATT 5dB 6 Tracking generator output 30dBm Refer to Fig 2 page 23 High 7 Adj item BPH Adjust ᲤᲤ 8 Spectrum analyzer setting Center f 469 950MHz Span 200MHz RBW 100kHz VBW 100kHz ATT 5dB 9 Tracking generator output 30dBm Refer to Fig 3 page 23 2 Squelch Tight Wid...

Page 28: ... ᲤᲤ 6 SSG output 124dBm 0 14µV Narrow Center 7 Adj item SQOC N icon apper Adjust ᲤᲤ 8 SSG output 124dBm 0 14µV SSG MOD 1kHz SSG DEV 1 5kHz 4 RSSI writing 1 Frequency 435 050MHz 2 SSG output 53dBm 501µV SSG MOD 1kHz SSG DEV 3kHz RSSI value writing is performed by the Squelch open item center wide SSG output level is changed and ad justed after Squelch adjustment This adjustment should not turn the ...

Page 29: ... External speaker 2 GND GND TX RX unit X57 8130 24 B 2 Display Section Pin No Name I O Function CN901 1 SPGND AF GND 2 SPGND AF GND 3 SPOUT I AF out 4 SPOUT I AF out 5 8C I 8V DC supply 6 RXD O RXD PC serial data 7 PTT O PTT PC serial data 8 VOL O Volume 9 MICKEY O Microphone key 10 5C I 5V DC supply 11 CM O Microphone key check 12 ENCA O Encoder A 13 ENCB O Encoder B 14 DI O Data from LCD driver ...

Page 30: ...C789 IC712 O G I C858 C859 C860 C861 C863 R809 R822 R824 R825 R826 C801 C806 C810 C817 C822 C830 C832 C838 Q714 G S D R737 R739 R757 R758 R761 R765 R769 R770 R771 R772 R774 C749 C753 C763 C767 C774 C775 C776 IC708 IC711 O G I R817 R818 R819 R832 R833 R834 R841 R843 C816 C820 C827 C834 C850 Q704 Q705 Q712 R505 R507 R701 R702 R703 R704 R705 R706 R707 R708 R337 C508 C509 C702 C703 R749 C713 SPGND SPG...

Page 31: ...587 R813 C408 C409 C412 Q506 Q708 R508 R509 CN501 R520 R521 R529 R338 R340 R342 R344 R348 TH501 R351 TH703 C514 C524 C525 C333 C334 R377 C530 C342 C347 D301 C556 D305 D503 D504 C565 D314 D316 C575 IC303 C579 C857 R845 TX RX UNIT X57 8130 24 A 2 TX RX SECTION Component side view J79 0316 19 A 2 Component side Foil side Layer 1 Layer 2 PC BOARD Ref No Address IC302 3K IC303 8P IC707 9F IC708 7E IC71...

Page 32: ...2 R794 D505 D311 R796 7 1 C566 C567 D508 D509 C569 C570 C571 C574 C576 C578 R846 C582 C397 C399 X1 C784 C787 C788 IC710 3 1 4 5 C11 C14 C15 C563 C564 C855 R350 L703 C999 C405 C406 D306 D307 R381 C34 C38 C41 C46 C52 C53 C55 C56 C58 Q10 C68 C69 C71 C420 L320 D4 D7 D9 Q504 Q505 G1 S S D D G2 G1 G2 L507 L511 D10 L7 L10 L11 L23 L21 R534 R540 R541 R544 R545 R547 R556 R24 R25 R26 R29 Q5 R31 R34 C537 C539...

Page 33: ... 1 24 R744 R746 C724 C732 C734 C740 C745 C746 C748 C750 C754 R799 D702 D704 D705 D706 D709 D711 IC709 C790 C794 C797 C798 4 4 5 1 8 5 1 8 C799 C818 C825 C831 C840 C844 IC706 J701 EXT SP C836 C839 R830 TX RX UNIT X57 8130 24 A 2 TX RX SECTION Foil side view J79 0316 19 A 2 Component side Foil side Layer 1 Layer 2 TM 481A J79 0316 19 A 2 Ref No Address IC1 9I IC2 8F IC501 11F IC703 11M IC704 11L IC7...

Page 34: ... 8C 7 J901 D904 D906 D907 D908 D909 Q901 Q902 R914 R915 R918 R920 R921 R922 R923 R924 C901 C902 C912 C915 C916 C917 C918 C929 D901 D902 SPGND 1 22 SPGND SPOUT SPOUT 8C RXD PTT VOL MICKEY 5C CM ENCA ENCB DI DO CE CL BRI POWER MIC ME GND TX RX UNIT X57 8130 24 B 2 DISPLAY SECTION Component side view J79 0316 19 B 2 TX RX UNIT X57 8130 24 B 2 DISPLAY SECTION Foil side view J79 0316 19 B 2 PC BOARD TM...

Page 35: ...NIT X57 8130 24 B 2 DISPLAY SECTION Component side view J79 0316 19 B 2 TX RX UNIT X57 8130 24 B 2 DISPLAY SECTION Foil side view J79 0316 19 B 2 Component side Foil side Layer 1 Layer 2 Component side Foil side Layer 1 Layer 2 TM 481A J79 0316 19 B 2 J79 0316 19 B 2 Ref No Address D903 6K D904 6G D905 6O D906 4F D907 4G D908 4H D909 4I D910 4L D911 4J Ref No Address IC901 12K Q901 11F Q902 11F Q9...

Page 36: ...0 C45 2p R29 220 L7 270n C35 22p L11 33n C38 5p L9 270n L23 180n C50 2p R33 270 L25 C52 3p L1 L18 47n D7 1SV278F IC704 NJM12904RB1 1 2 3 4 5 6 7 8 VCC SPLATTER FILTER W NI EVOL1 5C VCO CV VOLTAGE DROPPED SWITCHING OP AMP TCXO IDC DETECTION BUFFER AMP CK CPU54 DT CPU53 DT CPU53 HPF TX RX UNIT X57 8130 24 A 2 TX RX SECTION W NO EVOL2 PLLE CPU3 FRQO UL CPU21 CK CPU54 PLLE CPU3 8CL 8CL RIPPLE FILTER D...

Page 37: ...D508 509 IF AMP 50 4MHz 8R 8R IF SWITCH W NI EVOL1 EEPROM RF AMP MCU AFV AF MUTE AF MUTE VOLI EVOL13 AFM CPU50 WIDE TRIPLER RF BPF TUNING MIXER RF AMP 8RC CPU76 8TC CPU80 AMPSW CPU52 SPM CPU51 BRI 8RC CPU76 VOLO EVOL15 W NO EVOL2 MIC PC TV CM MICKEY VOL TV TX RX CPU20 QT DQT CPU1 EVLLD CPU8 TX DTMF UL CPU21 PLLE CPU3 XOUT CPU11 XIN CPU13 POWER MICMT CPU77 CK CPU54 DT CPU53 W NO EVOL2 PC TV W NI EV...

Page 38: ...O EVOL2 SQL AMP Q708 710 8C SB OVER VOLTAGE DETECTION SURGE ABSORPTION AF MUTE AF MUTE 8R POWER IC715 LA4600 1 2 3 4 5 6 7 8 9 10 PTT BRI RXD POWER VOL 8C 5C DO CL CE DI MICKEY ENCB CM ENCA DC SWITCH 8R DC SWITCH 8T PROTECTION BRI AUDIO AMP RD00HVS1 T113 AMPSW CPU52 MIC 8TC CPU80 SPM CPU51 8RC CPU76 BRI PC TV VOLO EVOL15 W NO EVOL2 2SC4617 S Q502 8 9 10 11 12 13 14 IC709 BA10324AFV DTMF IN CPU95 I...

Page 39: ...1 COM2 SEG13 COM1 RESISTOR COM3 SEG24 SEG1 LCD SEG17 SEG27 SEG29 SEG4 SEG26 SEG31 SEG5 SEG14 SEG18 SEG19 VARIABLE SEG8 SEG12 SEG2 SEG20 LED TX RX UNIT X57 8130 24 B 2 DISPLAY SECTION SEG22 MR SEG0 SEG16 COM0 SEG6 SEG28 SEG25 SEG30 ENCODER LCD DRIVER KEY BACKLIGHT SWITCH BRIGHTNESS FUNCTION SWITCH D903 905 LCD BACKLIGHT SWITCH DC SWITCH LED 2 3 4 5 6 7 8 8 9 10 11 12 13 14 15 16 17 18 Func CALL VFO...

Page 40: ...OWER D903 D905 1SS372F D709 X1 KS2 MIC MIC AMP GND 5C CM ENCA VOL ME GND AMP L77 1944 05 TCXOMOD TCXO ENCB COM0 3 SEG0 31 KI2 KI1 KI3 KS1 KS2 SW 2SB1132 Q R Q903 LCD ILLUMINATION D906 D911 B30 2337 05 UMG3N Q904 BRI SW 8C MICMT MUTE SW 5C DET D HSB N 8CL DA2S101 D8 PUMP CHARGE D708 DA2S101 IC704 NJM12904RB1 FILTER SPLATTER 8C SPGND IC706 1 4 BA10324AFV AMP SUM 8C DTMO 5C M62363FP F IC705 3 8 BA103...

Page 41: ...n frequency X 350 050 420 045MHz X 400 000 469 995MHz TX RX 400 000 469 995MHz SW RF BPF 5M IF Q712 HSC277 EXT 16 8MHz 3SK318 2SJ645 5V VCO RF BPF 8R IC714 MCH3914 7 H EEPSDT IC501 SW RT1N141U T111 AMPSW Q715 RSSI SQIN 8C TA31136FNG AMP COMM AMP D9 D10 HSB88AS E DETECTOR IC303 NJM12904RB1 AMP RSSI RT1N141U T111 5V FB 5C MCH3914 7 H RA60H40471101 L71 0655 05 L72 0993 05 L72 0999 05 8T BSB 8 000MHz ...

Page 42: ...urements in the AF section connect the AC level meter AG is set so that MIC input becomes 3kHz 1 5kHz Wide Narrow DEV at 1kHz MOD D CF501 CF502 450kHz 7 IC706 TX RX Unit S IC501 5 49 95MHz 9 IC703 G1 16 1 Center Frequency W 122 5dBm N 122 0dBm W 122 0dBm N 121 5dBm W 109 0dBm N 108 5dBm W 110 5dBm N 109 5dBm W 0 21Vrms N 0 11Vrms W 0 38Vrms N 0 19Vrms W 117 5dBm N 117 5dBm W 106 5dBm N 105 0dBm W ...

Page 43: ...8Ω by the front panel AF VOL control Q6 meter B SINAD TX RX Unit Q9 9 Q10 Power Module Q303 D9 D10 TX RX Unit S Audio Frequency D TX RX Unit VCO CF501 CF502 450kHz G IC501 D306 D307 ANT 0 5dBm 45W W 93 0dBm N 92 0dBm W N 0 55Vrms W N 0 46Vrms W N 0 43Vrms W N 0 47Vrms W N 0 49Vrms W N 10mVrms W N 0 88Vrms W N 0 64Vrms 1 0dBm 14 J1 IC705 12 Q706 8 9 13 8ohm 10 IC709 7 IC715 IC709 5 1 IC709 IC709 15...

Page 44: ...itry Double conversion superheterodyne Intermediate Frequency 1st 2nd 49 95MHz 450kHz Sensitivity 12dB SINAD Wide 0 20µV or less Narrow 0 25µV or less Selectivity 6dB Wide 12kHz or more Narrow 10kHz or more 60dB Wide 30kHz or less Narrow 24kHz or less Squelch Sensitivity 0 1µV or less Audio Output 8 5 distortion 2W or higher Audio Output Impedance 8 TRANSMITTER Power Output High 45W Low Approx 25W...

Page 45: ...R770 R771 R772 R774 C749 C753 C763 C767 C774 C775 C776 IC708 IC711 O G I R817 R818 R819 R832 R833 R834 R841 R843 C814 C816 C820 C827 C834 C850 Q704 Q705 Q712 R504 R505 R507 R701 R702 R703 R704 R705 R706 R707 R708 R337 C508 C509 C702 C703 R749 C713 SPGND SPGND SPOUT SPOUT 8C RXD PTT VOL MICKEY 5C CM ENCA ENCB DI DO CE CL BRI POWER MIC ME GND 1 22 R752 R753 C718 C719 C720 R763 R767 R773 R775 R776 R7...

Page 46: ...0 D4 D7 D9 Q504 Q505 G1 S S D D G2 G1 G2 L507 L511 D10 L7 L10 L11 L23 L21 R534 R540 R541 R544 R545 R547 R556 R24 R25 R26 R29 Q5 R31 R34 C537 C539 R42 R43 R45 C557 C558 C561 D506 C568 C573 C60 R512 R514 R525 C517 C519 C520 C521 C522 Q6 Q9 C527 C533 IC501 R522 C36 C39 C45 C51 C57 D3 L502 R502 L6 L24 C506 CD501 R28 Q4 R30 R32 R38 C20 C21 C23 C25 C27 C28 C29 C61 C804 C811 C1 C3 C4 C5 C7 C9 10 11 1 20 ...

Page 47: ...6 C929 D901 D902 R912 SPGND 1 22 SPGND SPOUT SPOUT 8C RXD PTT VOL MICKEY 5C CM ENCA ENCB DI DO CE CL BRI POWER MIC ME GND TX RX UNIT X57 8130 24 B 2 DISPLAY SECTION Component side view J79 0316 19 B 2 TX RX UNIT X57 8130 24 B 2 DISPLAY SECTION Component side view J79 0316 19 B 2 TX RX UNIT X57 8130 24 B 2 DISPLAY SECTION Foil side view J79 0316 19 B 2 TX RX UNIT X57 8130 24 B 2 DISPLAY SECTION Foi...

Page 48: ...TCH D702 704 706 8TC CPU80 8RC CPU79 8R RX 8R IF SWITCH W NI EVOL1 EEPROM RF AMP 5C MOD DETECTION MODULATION 8C VOLTAGE DETECTION INT 1 2Vcc MCU DC SWITCH SB 8C AGC MIC MUTE AFV AF MUTE AF MUTE W NO EVOL2 SQL AMP T R SWITCH VOLI EVOL13 PLL IC AFM CPU50 D7 T R SWITCH Q708 710 8C SB OVER VOLTAGE DETECTION 16 8MHz BEAT SHIFT TCXOMOD RIPPLE FILTER RF AMP WIDE SURGE ABSORPTION AF MUTE TRIPLER RF BPF TU...

Page 49: ...ection SP MCH3914 7 H BL LCD DRIVER IC901 PT6554LQ LCD DISPLAY POWER 5C BRI CL POWER D903 D905 1SS372F D709 EEPSDT X1 IC501 SW RT1N141U T111 AMPSW Q715 RSSI SQIN 8C KS2 MIC MIC TA31136FNG AMP COMM AMP D9 D10 HSB88AS E DETECTOR IC303 NJM12904RB1 AMP RSSI RT1N141U T111 5V FB AMP GND 5C CM ENCA VOL ME GND AMP L77 1944 05 5C MCH3914 7 H RA60H40471101 L71 0655 05 L72 0993 05 L72 0999 05 8T TCXOMOD TCXO...

Page 50: ...ency IC705 D TX RX Unit VCO MIC To make measurements in the AF section connect the AC level meter AG is set so that MIC input becomes 3kHz 1 5kHz Wide Narrow DEV at 1kHz MOD D CF501 CF502 450kHz 7 G IC706 TX RX Unit S IC501 5 49 95MHz D306 D307 9 IC703 G1 16 1 ANT Center Frequency 0 5dBm 45W W 122 5dBm N 122 0dBm W 122 0dBm N 121 5dBm W 109 0dBm N 108 5dBm W 110 5dBm N 109 5dBm W 0 21Vrms N 0 11Vr...

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