sony_icf_sc1_service_manual 电路图 维修原理图.pdf

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1、MICROFILM ICF-SC1/SC1PC SERVICE MANUAL PLL SYNTHESIZED SCANNING RECEIVER SPECIFICATIONS US Model Circuit system : Triple conversion superheterodyne Frequency range : 25.000 1300.000MHz (excluding cellular phone band : 823.980 849.020 MHz and 868.980 894.020 MHz) Detection mode : AM, NFM, WFM Speaker

2、 :Approx. 36 mm (1 7/16 inches) dia., 8 ohms Power output : 150mW(at 10% harmonic distortion Output : jack (monaural minijack) Power requirements : DC 6V, four size AA (R6) batteries External power source : DC 6V Dimensions : Approx. 64 x 177 x 44.3 mm (w/h/d) (2 5/8 x 7 x 1 3/4 inches) incl. projec

3、ting parts and controls, not including the helical antenna and the belt holder Mass :Approx. 252g (8.9 oz) Approx. 382g (13.5 oz) incl. alkaline batteries, helical antenna, and the belt holder Supplied Accessories AC power adaptor (1) Earphone (1) Belt holder (1) Helical antenna (1) Frequency guideb

4、ook (1) CD-ROM (1) (ICF-SC1PC only) Serial port connecting cable (1) (ICF-SC1PC only) Clamp filter (1) (ICF-SC1PC only) Design and specifications are subject to change without notice. Ver 1.01998.03 RadioFans.CN 2 Specifications . 1 1.GENERAL Location and Function of Controls . 3 2.DISASSEMBLY 2-1.

5、Helical Antenna Removal . 10 2-2. Cabinet (Rear) Assy Removal . 10 2-3. Microcomputer Board, IF Board, RF Board Removal .11 3.TEST MODE. 12 4.ELECTRICAL ADJUSTMENS. 13 5.DIAGRAMS 5-1.Explanation of IC Terminals . 15 5-2.Block Diagram. 17 5-3.Printed Wiring Boards IF Section . 19 5-4.Schematic Diagra

6、m IF Section . 21 5-5.Printed Wiring Boards Microcomputer Section 23 5-6.Schematic Diagram Microcomputer Section. 25 5-7.Printed Wiring Boards RF Section . 27 5-8.Schematic Diagram RF Section (1/2) . 39 5-9.Schematic Diagram RF Section (2/2) . 31 6.EXPLODED VIEW. 35 7.ELECTRICAL PARTS LIST. 36 SAFET

7、Y-RELATED COMPONENT WARNING! COMPONENTS IDENTIFIED BY MARK ! OR DOTTED LINE WITH MARK ! ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY. TABL

8、E OF CONTENTS RadioFans.CN 3 SECTION 1 GENERAL LOCATION AND FUNCTION OF CONTROLS FRONT This section is extracted from instruction manual. RadioFans.CN 4 SIDE/REARDISPLAY RadioFans.CN 5 RadioFans.CN 6 RadioFans.CN 7 RadioFans.CN 8 RadioFans.CN 9 RadioFans.CN 10 SECTION 2 DISASSEMBLY Note : Follow the

9、 disassembly procedure in the numerical order given. 2-1. HELICAL ANTENNA REMOVAL 2-2. CABINET (REAR) ASSY REMOVAL 1 Helical antenna 1 4 3 3 3 Battery case lid Cabinet (Rear) assy 2 Screws 2 Screws Claw Claws Claws RadioFans.CN 11 2-3. MICROCOMPUTER BOARD, IF BOARD, RF BOARD REMOVAL 7 Remove solder

10、9 CN401 (16pin) IF board Coaxial connector !? !? !? !? !? !? 8 !? !? !? RF board Chassis Cabinet (Front) assy Microcomputer board IF board RF board 5 Screws 5 Screws 2 Remove solder 1 Knob (VOL) 4 6 3 CN402 (22pin) RadioFans.CN 12 Reading the S-Curve voltage for scan-stop The ICF-SC1 and SC1PC have

11、a scan-stop function used to scan for the correct frequency. Scanning continues until the squelch turns off (when a signal is received). However, just setting the squelch off as condition does not guarantee that the scan-stop function will always stop at the correct frequency. (It might for instance

12、 deviate 1 step to an adja- cent frequency.) So scan-stop is set to trigger only at the correct frequency, by check- ing the DC voltage component (S-curve voltage) of the FM detec- tor output. The DC voltage component of the FM detector output may vary however, due to variations in the parts compone

13、nts of the FM de- tector circuit or deviations in the local oscillator frequency. There- fore, once repair or alignment is complete, read the DC voltage component of the RF detector output while it is input with an IF signal from a signal generator, and use that value as a reference to write data on

14、 the EEPROM. Two types of writing are performed on the EEPROM since there are two types of FM detectors. WFM n for WFM NFM n for NFM, AM Refer to the following for information on the write method and on the signal input method using a signal generator. LCD (all lamps on) All LCD lamps up when the th

15、ree EXE, and SCAN keys are simultaneously held down while the power is off. Reading the S-Curve voltage component 1. Input method for S-Curve voltage component read mode Simultaneously hold down the MODE, STEP and BAND keys for at least 1second while power is off. The set (ICF-SC1/SC1PC) power turns

16、 on and a display as shown below appears. 2. Quitting S-Curve voltage read mode Press the POWER button. Note :When set in S-Curve voltage read mode, do not connect any- thing to the antenna terminal while the power to the RF sec- tion is on. (An unwanted signal might otherwise be received through th

17、e antenna.) However when set, a check can be made that a broadcast RF carrier wave was received. (1) Turn the power on as usual and receive a broadcast signal. (2) Turn off the power and set in read mode with MODE + STEP + BAND. (3) Write can be checked with SVC or SCAN since the broad cast signal r

18、eceived in (1) can be heard. In the following cases the message “TRY AGAIN” appears and writing is disabled. (1) When the Squelch is closed. (2) When the S-curve voltage that was read, is not within 0.5V to 1.3V. SECTION 3 TEST MODE S-Curve voltage write method Signal input method using signal gener

19、ator. 1. In NFM (1) Connect a signal generator to TP1 by way of a 0.01F capaci- tor. (2) Receive NFM (Receive frequency does no matter) (3) Input 455kHz from the signal generator, 90 to 100dB, modu- lation 30%, mod frequency of 1kHz. (4) Write the COMPN terminal voltage onto the ROM. (5) Press the S

20、VC button. When data is written, a display as shown below appears. 2. In WFM (1) Connect a signal generator to TP4 by way of a 0.01F capaci- tor. (2) Receive WFM (Receive frequency does no matter) (3) Input 10.7MHz from the signal generator, 90 to 100dB, fre- quency deviation 22.5kHz, mod frequency

21、of 1kHz. (4) Write the COMPW terminal voltage onto the ROM. (5) Press the SCAN button. When data is written, a display as shown below appears. 16 0.01 C407 1000P MIX IN IC401 TA31136FN 45M Xtal filter TP1 S.G. 10 0.01 S.G. C434 0.01 FM RF IN IC402 CXA1111N RF BOARD TP4 NFM 0 . 9 4 Voltage (V) WFM 0

22、. 8 7 Voltage (V) IF BOARD (Rear side) CN402 COMPN COMPW Adjustment Location : RadioFans.CN 13 SECTION 4 ELECTRICAL ADJUSTMENTS Setting : trackig generator (GND) spectrum analyzer (GND) FM RF signal generator (GND) digital voltmeter (GND) RF BOARD (SINGLE) ADJUSTMENT 1. 2nd local oscillator Adjustme

23、nt Procedure : (1) Connect a tracking generator to TP10 and a spectrum ana- lyzer to TP6. (TG level = 40 to 50dBm, spectrum analyzer span = 200MHz) (2) Receive a 600MHz signal. (3) Repeatedly adjust CT303, 304 and 305 for an optimal wave- form at center frequency of 277.5MHz. (4) Receive the 25MHz s

24、ignal. (5) Adjust the 2nd local oscillator to 555MHz with CT302. (spectrum analyzer span = 10kHz) 2. 1st local oscillator Adjustment Procedure : (1) Connect a spectrum analyzer to TP5. (2) Receive a 767.5MHz signal. (3) Adjust the CT301 so that 1st local oscillator = 1000MHz (spectrum analyzer span

25、= 10kHz) 3. 1st IF (low) Adjustment Procedure : (1) Connect a tracking generator to TP5 and a spectrum analyzer to TP7. (2) Recive a 500MHz signal. (3) Repeatedly adjust CT201, 202 and 203 for an optimal wave- form (ladder shape) at center frequency of 232.5MHz. (TG level = 30 to 40dBm, spectrum ana

26、lyzer span = 200MHz) Adjustment Location : RF board (see page 14) IF BOARD (SINGLE) ADJUSTMENT 1. 3rd local oscillator Adjustment Procedure : (1) Connect a spectrum analyzer to TP2. (2) Receive a 49.975MHz signal. (3) Adjust the CT401 so that the 3rd local oscillator = 44.5500MHz. (spectrum analyzer

27、 span = 10kHz) (4) Recive a 50.0125MHz signal. (5) Adjust the 3rd local oscillator to 44.5425MHz with RV401. (spectrum analyzer span = 10kHz) Adjustment Location : IF board (see page 14) RF & IF BOARD (COMBINATION) ADJUSTMENT 1. 2nd IF (narrow) Adjustment Procedure : (1) Connect a tracking generator

28、 to RF (RF board) TP6 and con- nect a spectrum analyzer to IF (IF board) TP1 by way of a 0.5pF capacitor. (2) Receive a 29MHz signal. (3) Align for an optimal waveform with T206. (ladder waveform with minimum ripple) (TG level = 50dBm, spectrum analyzer Center freq. = 45MHz, span = 100kHz) 2. 2nd IF

29、 (wide) Adjustment Procedure : (1) Connect a tracking generator to RF (RF board) TP6 and con- nect a spectrum analyzer to IF (IF board) TP3. (2) Receive a 70MHz signal. (3) Adjust so the 45MHz is at maximum by using CT402 and T205. (TG level = 50dBm, spectrum analyzer Center freq. = 45MHz, span = 50

30、MHz) 3. AGC Adjustment Procedure : (1) Connect a FM RF signal generator to the BNC (ANT IN) connector. (2) Connect a digital voltmeter to RV403 center tap (COMMON). (IF board) (3) Receive a 122MHz signal (input level 80dEMF, AM, modu- lation 30%). (4) Adjust RV403 so that digital voltmeter reading i

31、s at 1.68 0.02V. Adjustment Location : RF, IF board (see page 14) * Use semirigid cable when connecting the tracking generator and spectrum analyzer to the circuit board. * Spectrum analyzer settings shown in the ( ) are reference values. RadioFans.CN 14 Adjustmen Location : RF BOARD (Front side) IF

32、 BOARD (Rear side) RF BOARD (Rear side) TP2 TP3 TP1 GND GND TP1 TP2 TP4 TP3 ANT IN (BNC connector) CT402 CT301 CT305 CT203 CT201 CT202 CT304 CT303 CT302 T206 T205 RV403 RV403 center tap (COMMON) RV401 CT401 TP5 TP6 TP7 TP10 RadioFans.CN 15 Pin No.Pin nameI/ODescription 1COMP-WIWFM S-curve voltage in

33、put (A/D input). 2BATTILow battery voltage detection input (A/D input). 3 7KS0 4OKey matrix output. 8AVDDPower supply for A/D converter. 9AVREFPower supply for A/D reference. 10AC-DETIExternal power supply detect terminal. 11LEDOLED drive. “H” : Lighting 12VSSGround. 13TESTITest mode terminal. “H” :

34、 Test mode 14LCDI“H” : Normal. (LCD display ON = H during PC operaion) 15BEEPOBeep signal output. 16SCANOScan signal output. “H” : Scan run 17DUBNot used (Open). 18WFMOWFM mode select. “H” : WFM mode 19D/A 0OD/A output bit 0 for minute step. 20D/A 1OD/A output bit 1 for minute step. 21STANDBYOStandb

35、y signal output. “H” : RS232C interface OFF 22MUTEOMute signal output. “H” : Mute ON 23 25COM0 2OLCD common output. 26COM3Not used (Open). 27BIASLCD bias terminal. 28 30VLC0 2LCD bias terminal. 31VSSGround. 32 62S0 30OLCD segment output. 63Not used (Open). 64AMOAM mode output. “H” : AM mode 65NFMONF

36、M mode output. “H” : NFM mode 66IF 1OIF selection output. 67RFORF selection output. 68MAINOMain power supply ON/OFF control. 69FILTEROSerial latch output for filter selection. 70PLLOSerial latch output for PLL selection. 71ROMOClock output for EEPROM. 72DOISerial data input from EEPROM. 73DIOSerial

37、data output to EEPROM. 74CLKOSerial clock output. 75RXDIRXD input from RS232C interface. 76TXDOTXD output to RS232C interface. 77CTSOCTS output to RS232C interface. 78IC (GND)Ground. 79XM2Main clock oscillator (4.194304MHz). 80XM1Main clock oscillator (4.194304MHz). 81VDDPower supply (+4.0V). 82XS2S

38、ub clock oscillator (32.768kHz). 83XS1Sub clock oscillator (32.768kHz). 84RESETISystem reset terminal. 85OFF-DETILow power detection OFF input. “L” : OFF SECTION 5 DIAGRAMS 5-1. EXPLANATION OF IC TERMINALS IC604 PD78064BGC (SYSTEM CONTROL) RadioFans.CN 16 Pin No.Pin nameI/ODescription 86L-DETIPLL lo

39、ck detect. “L” : Lock 87N-DETISquelch detection input. “L” : 88RTSIRTS input from RS232C interface. 89CONNECTIPC connect check signal input. 90REMOTEIPC connect check signal input. 91Not used (Open). 92Not used (Open). 93 98KR5 0IKey matrix input. 99VSSGround. 100COMP-NINFM (AM) S-curve voltage inpu

40、t (A/D input). RadioFans.CN 17 18 ICF-SC1/SC1PC Signal path. F 5-2. BLOCK DIAGRAM RadioFans.CN 21 22 5-4. SCHEMATIC DIAGRAM IF SECTION ICF-SC1/SC1PC Note: All capacitors are in F unless otherwise noted. pF: F 50 WV or less are not indicated except for electrolytics and tantalums. All resistors are i

41、n and 1/4 W or less unless otherwise specified. U : B+ Line. Power voltage is dc 6 V and fed with regulated dc power supply from external power voltage jack (J402). Voltages are dc with respect to ground under no-signal (detuned) conditions. no mark : WFM/AM/NFM () : AM/NFM : NFM Voltages are taken

42、with a VOM (Input impedance 10 M). Voltage variations may be noted due to normal produc- tion tolerances. Signal path. F r Refer to page 33 for IC Block Diagrams. RadioFans.CN 25 26 r WAVEFORMS 2 IC604 & VOLT/DIV : 1 V AC TIME/DIV : 0.2 msec 1 IC604 * VOLT/DIV : 0.2 V AC TIME/DIV : 20 msec 0.5Vp-p 3

43、2.7 sec 2Vp-p 0.24 sec Note: X : parts extracted from the component side. D: Chip components extracted from the rear side. r: Through hole. b : Pattern from the side which enables seeing. (The other layers patterns are not indicated.) Caution: Pattern face side:Parts on the pattern face side seen fr

44、om (Conductor Side)the pattern face are indicated. Parts face side:Parts on the parts face side seen from (Component Side)the parts face are indicated. Note: All capacitors are in F unless otherwise noted. pF: F 50 WV or less are not indicated except for electrolytics and tantalums. All resistors ar

45、e in and 1/4 W or less unless otherwise specified. U : B+ Line. Power voltage is dc 6 V and fed with regulated dc power supply from external power voltage jack (J402). Voltages and waveforms are dc with respect to ground under no-signal (detuned) conditions. no mark : WFM/AM/NFM () : AM/NFM : NFM IC

46、F-SC1/SC1PC r Refer to page 33 for IC Block Diagrams. 5-6. SCHEMATIC DIAGRAM MICROCOMPUTER SECTION Voltages are taken with a VOM (Input impedance 10 M). Voltage variations may be noted due to normal produc- tion tolerances. Waveforms are taken with a oscilloscope. Voltage variations may be noted due

47、 to normal produc- tion tolerances. Circled numbers refer to waveforms. RadioFans.CN 29 30 Note: All capacitors are in F unless otherwise noted. pF: F 50 WV or less are not indicated except for electrolytics and tantalums. All resistors are in and 1/4 W or less unless otherwise specified. U : B+ Line. Power voltage is dc 6 V and fed with regulated dc power supply from external power voltage jack (J402). Voltages are dc with respect to ground unde