IC-PCR100_serv (1).pdf

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1、SERVICE MANUAL COMMUNICATION RECEIVER FOR COMPUTER iC-pcr100 REPAIR NOTES 1. Make sure a problem is internal before disassembling the receiver. 2.DO NOTopen the receiver until the receiver is discon- nected from its power source. 3.DO NOTforce any of the variable components. Turn them slowly and smo

2、othly. 4.DO NOTshort any circuits or electronic parts. An insu- lated tuning tool MUST be used for all adjustments. 5.DO NOTkeep power ON for a long time when the receiver is defective. 6.READthe instructions of test equipment thoroughly before connecting equipment to the receiver. INTRODUCTIONDANGE

3、R This service manual describe the latest service information for the IC-PCR100 COMMUNICATION RECEIVER FOR COMPUTER at the time of publication. NEVERconnect the receiver to an AC outlet or to a DC power supply that uses more than 16 V. Such a connection could cause a fire hazard and/or electric shoc

4、k. DO NOTexpose the receiver to rain, snow or any liquids. DO NOTreverse the polarities of the power supply when connecting the receiver. DO NOTapply an RF signal of more than 20 dBm (100 mW) to the antenna connector. This could damage the receivers front end. Be sure to include the following four p

5、oints when ordering replacement parts: 1. 10-digit order numbers 2. Component part number and name 3. Equipment model name and unit name 4. Quantity required 1130004200 S.ICTC4S66FIC-PCR100 MAIN UNIT 1 piece 8810008660 Screw PH B0 3 8 NI-ZU IC-PCR100 CHASSIS4 pieces Addresses are provided on the ins

6、ide back cover for your convenience. ORDERING PARTS To upgrade quality, any electrical or mechanical parts and internal circuits are subject to change without notice or obligation MODEL IC-PCR100 Europe U.K. Canada U.S.A-1 Other EUR UK CAN USA-1 OTH VERSIONSYMBOL TABLE OF CONTENTS SECTION 1 SPECIFIC

7、ATIONS SECTION 2INSIDE VIEWS SECTION 3DISASSEMBLY INSTRUCTIONS SECTION 4CIRCUIT DESCRIPTION 4 - 1?RECEIVER CIRCUITS. . 4 - 1 4 - 2?PLL CIRCUITS. 4 - 4 4 - 3?POWER SUPPLY CIRCUITS. 4 - 5 4 - 4?CPU PORT ALLOCATIONS . 4 - 6 SECTION 5ADJUSTMENT PROCEDURES 5 - 1?PREPARATION BEFOR SERVICING . . 5 - 1 5 -

8、2?PLL ADJUSTMENTS . 5 - 3 5 - 3?IF PEAK AND TOTAL GAIN ADJUSTMENTS . 5 - 5 5 - 4?SOFTWARE ADJUSTMENTS . 5 - 7 SECTION 6PARTS LIST SECTION 7MECHANICAL PARTS AND DISASSEMBLY SECTION 8SEMI-CONDUCTOR INFORMATION SECTION 9BOARD LAYOUTS 9 - 1?MAIN UNIT. 9 - 1 SECTION 10BLOCK DIAGRAM SECTION 11VOLTAGE DIAG

9、RAM 11 - 1?MAIN UNIT . 11 - 1 MGENERAL Frequency range: *Specifications guaranteed 0.51300 MHz only Mode: AM, FM, WFM Frequency stability: 5 ppm (at 1300 MHz: 0C to +50C; +32F to +122F) Frequency resolution: 1 kHz (minimum) Power supply requirement: 13.8 V DC 15 % for receiver unit; or supplied AC a

10、daptor (negative ground) Current drain (at 13.8 V DC): Power ON (PC power OFF)0.1 A Max. audio0.7 A Standby (squelched)0.6 A Usable temperature range: 0C to +50C; +32F to +122F Antenna connector: BNC (50 ) RS-232C connector: D-sub 9-pin (female) Dimensions : 131(W)35(H)164.1(D) mm; 5532(W)138(H)6153

11、2(D) inch Weight: approx. 0.5 kg; 1 lb 2 oz MRECEIVER Receive system: Triple-conversion superheterodyne Intermediate frequency: 1st266.7 MHz 2nd10.7 MHz 3rd450 kHz (except WFM) Sensitivity (typical)*: Squelch sensitivity: (at threshold) Selectivity (typical): WFM230 kHz/6 dB WFM/FM/AM50 kHz/6 dB FM/

12、AM15 kHz/6dB FM/AM/SSB/CW 6 kHz/6 dB Max audio output: Mono200 mW (at 10% distortion with an 8 load)Stereo100 mW External speaker connector: 3-conductor 3.5(d) mm (18)/48 Frequency MHz 0.5 1.799 1.8 27.999 28.0 29.999 30.0 49.999 50.0 699.999 700.0 1300.000 1 - 1 SECTION 1SPECIFICATIONS VersionFrequ

13、ency Range (MHz) 0.010 823.999* U.S.A.-1849.001 868.999 894.001 1300.000 Europe, U.K. 0.010 1300.000* Canada Other FM 0.5 V 0.32 V 0.4 V AM 2.5 V 1.8 V 1.0 V 1.3 V WFM 0.79 V 1.0 V *FM and WFM are measured at 12 dB SINAD; AM is measured at 10 dB S/N.; 230 kHz (for WFM), 15 kHz (for FM) and 6 kHz (fo

14、r AM) passband widths are selected. Frequency MHz 0.5 1.799 1.8 27.999 28.0 29.999 30.0 49.999 50.0 699.999 700.0 1300.000 FM 0.63 V 0.5 V 0.63 V WFM 5.6 V 10 V AM 1.8 V 0.89 V 0.71 V 0.89 V 2 - 1 SECTION 2INSIDE VIEWS MAIN UNIT Bottom view Top view 0.011.8 MHz RF filter circuit 1.815 MHz RF filter

15、circuit 1530 MHz RF filter circuit VCO3 circuit Reference oscillator (X5: CR-629 12.8 MHz) VCO1, VCO2 circuits AGC control circuit AGC amplifier (Q45: 2SC4211) FM discriminator (X2: CDBCA450CX24) CPU (IC21: HD6433644A) IF 15 kHz filter (FI7: CFWS450E) IF 6 kHz filter (FI6: CFWS450HT) AM demodulator

16、(D63: 1SS372) FM 3rd LO signal (X1: CR-630 12.5 MHz) 150300 MHz RF filter circuit 350700 MHz RF filter circuit 7001300 MHz RF filter circuit AF amplifier (IC23: M62429) AF power amplifier (IC25: NJM2073) 0.011.8 MHz RF filter circuit 3050 MHz RF filter circuit 50150 MHz RF filter circuit 1st mixer (

17、IC4: PC2721) PLL IC (IC8: MC145220) WFM demodulator IC (IC7: LA1832M) FM demodulator IC (IC10: TA31136) IF amplifier (Q29: 3SK131) EEPROM (IC20: X25020SI) 2nd mixer (IC5: PC2721) HF RF amplifier (Q12: 2SK2171) 3 - 1 SECTION 3DISASSEMBLY INSTRUCTIONS Removing the cover panel 1 Unscrew 4 screws, A. 2

18、Disconnect the speaker jack J8. 3 Remove the cover panel in the direction of the arrow. Removing the antenna plug and shield U-plate 1 Unscrew the nut, B. 2 Remove the shield cover in the direction of the arrow. AA Cover panel J8 Shield L-plate Shield case D B Shield U-plate C C MAIN UNIT Chassis C

19、Removing the MAIN unit 1 Unscrew 7 screws from the MAIN unit, C (set screw, 3 mm), to separate the chassis and unit. 2 Remove the unit in the direction of the arrow. Removing the shield plate 1 Remove the shield plate in the direction of the arrow. 2 Unsolder 9 points, D, to separate the shield plat

20、e and MAIN unit. SECTION 4CIRCUIT DESCRIPTION 4 - 1 4-1 RECEIVER CIRCUITS 4-1-1 RF ATTENUATOR CIRCUIT The attenuator circuit attenuates the signal strength to approx. 20 dB to protect the RF amplifier from distortion when excessively strong signals are received. The RF signals from the antenna conne

21、ctor are passed through or bypass the “L” type attenuator (R1, R3). The sig- nals are then applied to the RF filter circuit. 4-1-2 RF FILTER CIRCUIT The applied signals pass through either the low-pass filter or the high-pass filter circuits via the band switching diodes. RF signals below 50 MHz The

22、 RF signals below 50 MHz are passed through the low- pass filter (L1, L2, C7C11) via the band switching diode (D2). The filtered signals are applied to the HF RF circuit. RF signals above 50 MHz The RF signals above 50 MHz are applied to the high-pass filter (L172, C477, C478) after passing through

23、the band switching diode (D4). The filtered signals are then applied to the VHF/UHF RF circuit. 4-1-3 HF RF CIRCUIT The HF RF circuit amplifies the received signals within the range 0.0150 MHz and filters out-of-band signals. The HF RF circuit consists of three low-pass filters, three high-pass filt

24、ers and one RF amplifier. The filtered signals below 1.8 MHz from the RF filter circuit are passed through the low-pass filter (L3, L4, C14C16) between the band swithing diodes (D6, D35), and are then applied to the 1st mixer circuit (IC4) directly. The 1.814.999 MHz signals pass through the low-pas

25、s fil- ter (L6, L7, C21C25) and high-pass filter (L8, L9, C26C30) between the band switching diodes (D3, D7), and are then applied to the 1st mixer circuit after being amplified at the RF amplifier (Q12). The 1529.999 MHz signals pass through the low-pass filter (L10, L11, C33C37) and high-pass filt

26、er (L11, L12, C38C42) between the band switching diodes (D90, D91), and are then applied to the 1st mixer circuit via the RF ampli- fier circuit (Q12). The 3049.999 MHz signals pass through the high-pass fil- ter (L14, L15, C45C49) between the band switching diodes (D8, D5), and are then applied to

27、the 1st mixer circuit via the RF amplifier circuit (Q12). Filters 4-1-4 VHF/UHF RF CIRCUIT The VHF/UHF RF circuit amplifies the received signals with- in the range 501300 MHz and filters out-of-band signals. The VHF/UHF RF circuit consists of 4 bands of filter circuits with an RF amplifier for each.

28、 The 50149.999 MHz signals from the RF filter pass through high-pass filter (D11, L17, C53C55, D12, D82, D83, L18, C57) via the band switching diode (D10), and are then amplified at the RF amplifier (Q8) between the tunable bandpass filters (D13, D80, L19L21, D14, D81, L23L25). The filtered signals

29、are applied to the 1st mixer circuit (IC4) via the band switching diode (D15). For improving the characteristic of the bandpass filter circuit, the shift switch (Q31) shifts the cut off frequency of the high- pass filter (D12, D82, D83, L18, C57). The shift switch (Q31) is controlled by the VCO 1 si

30、gnal from the CPU (IC21). Receive freq. SW diode Filter select Components (MHz)signal 0.011.799 1.814.999 15.029.999 30.049.999 D6, D35 D3, D7 D90, D91 D8, D5 B0 B1 B2 B3 L3L5, C14C17 L6L9, C21C30 L10L13, C33C42 L14, L15, C45C49 RF filter and amplifier circuits 0.0150 MHz 50150 MHz 150350 MHz 350700

31、 MHz 7001300 MHz 501300 MHz 1.815 MHz 1530 MHz 0.011.8 MHz 3050 MHz Tuned BPF ATTAGC Tuned BPF Tuned BPF Tuned BPF HPF Tuned BPF Tuned BPF Tuned BPF Tuned BPF HPF HPF LPF LPF LPF HPF RF Amp. RF Amp. To 1st mixer circuit RF Amp. LPF RF Amp. RF Amp. Q12 Q8 Q9 Q10 Q11 4 - 2 The 150349.999 MHz signals f

32、rom the band switching diode (D16) pass through the high-pass filter (L27L29, C69C74) and tunable bandpass filter (D18, L31L33), and are then amplified at the RF amplifier (Q9) and pass through another tunable bandpass filter (D19, L35L37). The filtered signals are applied to the 1st mixer circuit (

33、IC4) via the band switching diode (D20). The 350699.999 MHz signals from the band switching diode (D21) pass through the high-pass filter (L40, C92 C94) and tunable bandpass filter (D22, D23, L41, L42). The filtered signals are then amplified at the RF amplifier (Q10) and pass through the tunable ba

34、ndpass filters (D24, D77, L45L47). The filtered signals are applied to the 1st mixer circuit (IC4) via the band switching diode (D25). The 7001300 MHz signals from the band switching diode (D26) pass through the high-pass filter (L141, C110, C606) and 2-stage tunable bandpass filters (D27, D28, L163

35、, D29, D30, L51L53). The filtered signals are then amplified at the RF amplifier (Q11) and pass through the tunable bandpass filters (D31, D32, L56, L178). The filtered signals are applied to the 1st mixer circuit (IC4) via the band switching diode (D33). The tunable bandpass filters employ varactor

36、 diodes to tune the center frequency of the RF passband for wide bandwidth receiving and good image response rejection. These diodes are controlled by TUNV signal from the CPU (IC21, pin 54) via the tune controller (IC22b). Tunable bandpass filters 4-1-5 1ST MIXER CIRCUIT The 1st mixer circuit conve

37、rts the received RF signals into a fixed frequency of the 1st IF signal with a PLL output fre- quency. By changing the PLL frequency, only the desired frequency will pass through the bandpass filters at the next stage of the 1st mixer. The filtered RF signals are mixed with 1st LO signals at the 1st

38、 mixer circuit (IC4) to produce a 266.7 MHz 1st IF signal. The 1st IF signal is output from pin 5, and passed through the bandpass filter (FI1) to suppress unwanted harmonic components. The filtered 1st IF signal is applied to the IF cir- cuit. The 1st LO signals are generated at the VCO 1 (Q14, Q15

39、) or VCO 2 (Q18, Q19) circuit (according to the receiving fre- quency band) and are amplified at the buffer amplifier (IC26). The amplified signals are then applied to the 1st mixer (IC4, pin 2) directly or passed through the divider cir- cuit (IC6). 4-1-6 1ST IF AND 2ND MIXER CIRCUITS The 2nd mixer

40、 circuit converts the 1st IF signal into a 2nd IF signal. The filtered 266.7 MHz 1st IF signal from the bandpass filter (FI1) is amplified at the 1st IF amplifier (Q13) then mixed with the 2nd LO signal at the 2nd mixer circuit (IC5) to pro- duce a 10.7 MHz 2nd IF signal. The 2nd IF signal is passed

41、 through either 2 bandpass filters (FI2 or FI3; depending on the selected mode and bandwidth). The filtered 2nd IF sig- nal is amplified at the IF amplifier (Q29), then applied to the WFM demodulator or 3rd IF circuit. Receive freq.BPF selectVaractorRF (MHz)signaldiodesamp. 50.0149.999 150.0349.999

42、350.0699.999 700.01300.0 B4 B5 B6 B7 D11D14, D80D83 D18, D19 D22D24, D77 D27D32 Q8 Q9 Q10 Q11 IF and demodulator circuits 3rd Mixer IC10 2nd MixerBW: 50 kHz BW: 230 kHz 2nd LO IF Amp. IF Amp. 1st IF signal from 1st mixer (IC4) 3rd LO IF Amp. Limiter Active filter X2 450 kHz X1 10.25 MHz IC5 16 1110

43、13578 9 Q38 Q29 Q13 BPFFI2 FI3 FM Detector FI6 FI7 WFM Detector WFM FM AM HPF ANL IF Amp.Buffer Amp. Q43Q42 AM detector IC7 D63Q44, D52 to AF switch IC14 4 - 3 4-1-7 3RD MIXER CIRCUIT The 3rd mixer circuit mixes the 2nd IF signal and 3rd LO sig- nal to produce a 450 kHz 3rd IF signal (except WFM mod

44、e). The 10.7 MHz 2nd IF signal from the IF amplifier (Q29) is applied to the 3rd mixer section in the FM IF IC (IC10, pin 16). The applied signal is mixed with a 3rd LO signal gener- ated by X1 (10.25 MHz) to produce a 450 kHz 3rd IF signal. The 3rd IF signal is output from pin 3, and passed through

45、 one of 2 bandpass filters (FI6 or FI7) or bypassed, accord- ing to the selected mode after being amplified at the IF amplifier (Q38). The filtered or bypassed signal is applied to the each demodulator circuit (except WFM mode). Bandpass filter selection 4-1-8 DEMODULATOR CIRCUITS The demodulator circuit converts the 2nd IF signal into AF signals. 3 separate demodulator circuits are employed for each mode. (1) WFM mode The 10.7 MHz 2nd IF signal from the IF amplifier (Q29) is applied to the WFM demodulator circuit (IC7, pin 1). The IF signal