IC-R2_serv.pdf

《IC-R2_serv.pdf》由会员分享，可在线阅读，更多相关《IC-R2_serv.pdf（35页珍藏版）》请在收音机爱好者资料库上搜索。

1、SERVICE MANUAL COMMUNICATIONS RECEIVER for free by Radioamateur.EU INTRODUCTION DANGER ORDERING PARTS REPAIR NOTES This service manual describes the latest service information for the IC-R2 at the time of publication. NEVER connect the receiver to an AC outlet or to a DC power supply that uses more

2、than 3.5 V. Such a connection could cause a fire hazard and/or electric. DO NOT expose the receiver to rain, snow or any liquids. DO NOT reverse the polarities of the power supply when connecting the receiver. DO NOT apply an RF signal of more than 20 dBm (100mW) to the antenna connector. This could

3、 damage the re- ceivers front end. Be sure to include the following four points 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 8930046581LCD ContactIC-R2LOGIC UNIT5 pieces 8810009560 ScrewPH BO M

4、2x6 ZKIC-R2Chassis10 pieces Addresses are provided on the inside back cover for your convenience. 1. Make sure a problem is internal before disassembling the receiver. 2. DO NOT open the receiver until the receiver is disconnected from its power source. 3. DO NOT force any of the variable components

5、. Turn them slowly and smoothly. 4. DO NOT short any circuits or electronic parts. An insulated turning tool MUST be used for all adjustments. 5. DO NOT keep power ON for a long time when the receiver is defective. 6. READ the instructions of test equipment thoroughly before connecting equipment to

6、the receiver. To upgrade quality, all electrical or mechanical parts and internal circuits are subject to change without notice or oblig- ation. MODEL IC-R2 VERSION Europe Italy Taiwan U.S.A. Canada Other SYMBOL EUR ITA TPE USA CAN OTH OTH-1 for free by Radioamateur.EU SECTION1SPECIFICATIONS SECTION

7、2INSIDE VIEWS SECTION3DISASSEMBLY INSTRUCTIONS SECTION4CIRCUIT DESCRIPTION 4-1RECEIVER CIRCUITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1 4-2PLL CIRCUITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8、 . . . . . . . . . . . . . . . . . . .4-3 4-3POWER SUPPLY CIRCUITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-4 4-4PORT ALLOCATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-4 SECTI

9、ON5ADJUSTMENT PROCEDURES 5-1PREPARATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1 5-2PLL ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-3 5-3RECEIVE

10、R ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-5 SECTION6PARTS LIST SECTION7MECHANICAL PARTS AND DISASSEMBLY SECTION8SEMI-CONDUCTOR INFORMATION SECTION9BOARD LAYOUTS 9-1LOGIC UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . .

11、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-1 9-2RF UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-3 SECTION10BLOCK DIAGRAM SECTION11VOLTAGE DIAGRAM 11-1LOGIC UNIT . . . . . . . . . . . . . .

12、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-1 11-2RF UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-2 TABLE OF CONTENTS for free by Radioamateur.EU SECTION 1SPECIF

13、ICATIONS 1 - 1 MGENERAL Frequency range: Mode: FM, WFM, AM No. of memory channel: 450 channel Frequency stability: 6 ppm max. (10C to +60) Tuning steps: 5, 6.25, 10, 12.5, 15, 20, 25, 30, 50, and 100 kHz Anntena Impedance: 50 Power supply requirement: 2 AA(R6) Ni-Cd or alka- line cell Polarity: Nega

14、tive ground Frequency resolution: 5 kHz, 6.25 kHz Current drain (at 3.0 V): Rated audio170 mA typical Standby100 mA typical Power saved41 mA typical Usable temperature range: 10C to +60C ( 14F to +140F) Dimensions: 58(W) 86(H) 27(D) mm; (projections not included)2932(W) 338(H) 1116(D) in Weight(with

15、 antenna and battely): 170 (g); 6 (oz) External SP connector: 3-conductor 3.5(d) mm (18”) / 8 MRECEIVER Receiver system: Tripple super heterodyne Intermediate frequency : 1st266.7 MHz 2nd19.65 MHz 3rd450 kHz Sensitivity* : (except spurious points) * FM and WFM are measured at 12 dB SINAD; AM is meas

16、ured at 10 dB S/N. Squelch Sensitivity: Selectivity: AM / FMmore than 15 kHz / 6 dB less than 30 kHz / 60 dB WFMmore than 150 kHz / 6 dB Audio output power: 100 mW typical at 10 % distortion with an 8 load All stated specifications are subject to change without notice or obligation. Version EUR, U.K

17、., CAN, OTH, OTH-1 U.S.A. Receive Frequencies (MHz) 0.495 1309.995 0.495 823.995 849.000 868.995 894.000 1309.995 Frequency (MHz) 0.495 1.625 1.625 5.0 5.0 30.0 30.0 76.0 76.0 108.0 108.0 118.0 118.0 136.0 136.0 175.0 175.0 222.0 222.0 247.0 247.0 330.0 330.0 470.0 470.0 770.0 770.0 833.0 833.0 1309

18、.995 FM 0.56 V 0.4 V 0.56 V 0.79 V WFM 1.8 V 1.8 V 2.5 V AM 2.5 V 1.8 V 1.8 V 1.8 V Frequency (MHz) 0.495 1.625 1.625 5.0 5.0 30.0 30.0 76.0 76.0 108.0 108.0 118.0 118.0 136.0 136.0 175.0 175.0 222.0 222.0 247.0 247.0 330.0 330.0 470.0 470.0 770.0 770.0 833.0 833.0 1309.995 FM 0.56 V 0.4 V 0.56 V 0.

19、79 V WFM 5.6 V 5.6 V 5.6 V AM 2.5 V 1.8 V 1.8 V 1.8 V for free by Radioamateur.EU SECTION 2INSIDE VIEWS LOGIC UNIT 2 - 1 RF UNIT AF power amplifier (IC15: TA31056F) AF mute switch (Q37: 2SJ144) AF filter (Q30: XP6501) +3.2 regurater (IC4: S-81332H) 2nd mixer (IC10: PC2757T) IF amplifer (Q5: 2SC5231)

20、 FM IF IC (IC2: TA31136FN) PLL circuit PLL IC (IC3: PD3140GS) PLL reference oscillator (X1: CR593 19.200MHz) VCO circuit 1st mixer (IC1: PC2757T) BOTTOM VIEWTOP VIEW for free by Radioamateur.EU SECTION 3DISASSEMBLY INSTRUCTIONS 3 - 1 REMOVING THE REAR PANEL 1 Unscrew 2 screws, A. 2 Remove the rear p

21、anel in the direction of the arrow. REMOVING THE RF UNIT 1 Unscrew 1 screw, B. 2 Remove 1 knob, c. Unscrew 2 nuts, D and E. 3 Unsolder 5 points, F, and then remove the RF unit. REMOVING THE LOGIC UNIT 1 Unscrew 2 screws, G. 2 Unsolder 2 points, H, and then remove the LOGIC unit. A Rear panel B E D C

22、 RF unit F H G LOGIC unit for free by Radioamateur.EU SECTION 4CIRCUIT DESCRIPTION 4 - 1 4-1 RECEIVER CIRCUITS 4-1-1 ANTENNA SWITCHING CIRCUIT (RF UNIT) The RF signals from the antenna connector pass through the limitter (D68) and an attenuator (D69). The signals are then applied to the RF circuit t

23、he antenna switching circuit (D13, D73, D75) which suppress out-of-band signals. 4-1-2 RF CIRCUIT (RF UNIT) The RF circuit amplifies the received signals within the range of frequency coverage and filters out-of-band signals. (1) 0.495 MHz29.999 MHz RF signals (0.49529.999MHz) from an antenna switch

24、ing circuit (D73) pass through a low-pass filter (C511C515, L81, L82). The filtered signals are amplified at an RF ampli- fier (Q505) passing through each band-pass filter depending on the receiving frequency. The amplified signals are then applied to the 1st mixer circuit (IC1) after being amplifie

25、d at another RF amplifier (IC11) via the band switching diode(D71). The signals below 1.9 MHz pass through a low-pass filter (C534, C535, C657, C658, L88, L89) via the band switching diode (D66), and are then applied to the RF amplifier circuit (Q505) via the band switching diode (D67). The 1.9 MHz1

26、4.995 MHz signals pass through the band switching diode (D65) and band-pass filter (C522C531, L85L87, L91), and are then applied to the RF amplifier cir- cuit (Q505) via the band switching diode (D70). The 15 MHz29.995 MHz signals pass through the band switching diode (D63) and high-pass filter (C51

27、6C520, L83, L84) and are then applied to the RF amplifier circuit (Q505) via the band switching diode (D64). (2) 118 MHz174.995 MHz, 330 MHz832.995 MHz RF signals (118 MHz174.995 MHz, 330 MHz832.995 MHz) from an antenna switching diode (D75) are passed through each bandpass filter and RF amplifier,

28、and are then applied to the 1st mixer circuit (IC1) via the band switching diode (D71) and RF amplifier (IC11). The 118 MHz174.995 MHz signals pass through the band switching diode (D74) and low-pass filter (C8C13, C67, C416, L14, L57L59, L70), and are then amplified at RF amplifier (Q14). The ampli

29、fied signal passes through the tunable band-pass filters (D1, D2) and band switching diode (D25). The 330 MHz469.995 MHz signals are amplified at RF amplifier (Q35) via the band switching diode (D3) and band- pass filter (C19C23, C216, L2L5). The amplified signal passes through the tunable band-pass

30、 filters (D3, D4) and band switching diode (D29). The 470 MHz832.995 MHz signals are amplified at RF amplifier (Q24) via the band-pass filter (C32, C33, C35C37, C39, C144, C145), between the band switching diode (D11, D32). (3) 30117.995 MHz, 175329.995 MHz The 30 MHz117.95 MHz, 175 MHz329.995 MHz s

31、ignals pass through the low-pass filter (C40C43, C665, C666, L9, L10, L92), and are then applied to the RF amplifier (Q36). The amplified signals are amplified at the RF amplifier (IC11) via band switching diodes (D34, D71). The amplified signals are applied to the 1st mixer circuit (IC1). (4) 833 M

32、Hz1309.995 MHz The 833 MHz1309.995 MHz signals pass through the bandpass filter (C5, C4551, L11L13, L43), and are then applied to the RF amplifier (Q26). The amplified signals are amplified at the RF amplifier (IC11) via band switching diodes (D36). The amplified signals are applied to 1st mixer cir

33、cuit (IC1). 4-1-3 1ST MIXER CIRCUIT (RF UNIT) The 1st mixer circuit converts the received RF signals to 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

34、mixer. The filtered RF signals are mixed with 1st LO signals at the 1st mixer circuit (IC1) to produce a 266.7 MHz 1st IF signal. The 1st IF signal is output from pin 6, and passed through the bandpass filter (FI1) to suppress unwanted harmonic components. The filtered 1st IF signal is applied to th

35、e 2nd mixer circuit. The 1st LO signals are generated at the 1st VCO (Q28, Q30, D45) and are applied to the 1st mixer (IC1, pin 3) directly or passing through the doubler circuit (Q31) after being ampli- fied at the buffer amplifiers (IC4, Q40). 4-1-4 1ST IF AND 2ND MIXER CIRCUITS (RF UNIT) The 2nd

36、mixer circuit converts the 1st IF signal to a 2nd IF signal. The filtered 266.7 MHz 1st IF signal from the bandpass filter is mixed with the 2nd LO signal at the 2nd mixer circuit (IC10, pin 1) to produce a 19.65 MHz 2nd IF signal. The 2nd IF signal pass through (except WFM mode) or bypass (WFM mode

37、) the bandpass filter (FI3), and is then amplified at the 2nd IF amplifier (Q5). The amplified signal is applied to the demodulator circuit. 4-1-5 DEMODULATOR CIRCUITS (RF UNIT) The demodulator circuit converts the 2nd IF signal into AF signals. The 19.65 MHz 2nd IF signal from the 2nd IF amplifier

38、(Q5) is applied to the 3rd mixer section of the FM IF IC (IC2, pin 16) and is then mixed with the 3rd LO signal for conversion into a 450 kHz 3rd IF signal. for free by Radioamateur.EU 4 - 2 IC2 contains the 3rd mixer, limiter amplifier, quadrature detector and S-meter detector, etc. A frequency fro

39、m the PLL reference oscillator is used for the 3rd LO signal (19.20 MHz). (1) FM mode The 3rd IF signal is output from FM IF IC (IC2, pin 3) and passes through the ceramic bandpass filter (FI2). The fil- tered signal is fed back and amplified at the limiter amplifier section (pin 5), then demodulate

40、d AF signals at the quadra- ture detector section (pins 10, 11) and detector coil (L21). The demodulated AF signals are output from pin 9 and are applied to the AF circuit (LOGIC unit). (2) WFM mode The 3rd IF signal from the 3rd mixer bypasses the ceramic filter (FI2) and fed back to the limiter am

41、plifier section (pin 5). The amplified signal is demodulated at the quadrature detector section (pins 10, 11) and detector coil (L21). The AF signals are output from pin 9 and are applied to the AF cir- cuit (LOGIC unit). By connecting R55 to R54 in parallel, the output character- istics of pin 12,

42、“RSSI”, change gradually. Therefore, the FM IF IC can detect WFM components. (3) AM mode The filtered 3rd IF signal from the bandpass filter (FI2) is amplified at the 3rd IF amplifier (Q1). The amplified IF signal is applied to the AM detector circuit (Q4) to converted into AF signals, and the signa

43、ls are applied to the AF circuit (LOGIC unit). 4-1-6 AF AMPLIFIER CIRCUIT (LOGIC UNIT) The AF amplifier circuit amplifies the demodulated AF sig- nals to drive a speaker. While in FM mode, AF signals from the demodulator circuit (RF unit) are passed through the de-emphasis circuit (R118, C66, C68) w

44、ith frequency characteristics of 6 dB/octave, and are then applied to the pre-amplifier (Q31) via the band- pass filter (Q30). While in AM mode, AF signals are pass through the band- pass filter and are then applied to the pre-amplifier (Q31). While in WFM mode, AF signals are applied to the pre- am

45、plifier (Q31) directly. The pre-amplified AF signals pass through the AF mute cir- cuit (Q37) and are then applied to the electronic volume con- trol circuit (IC14, pin 6). The level controlled AF signals are output from pin 7 and applied to the AF power amplifier (IC15, pin 1) via the buffer amplif

46、ier (Q36). The power ampli- fied AF signals are applied to the internal speaker via the EXT SP jack. The electronic volume control circuit controls AF gain, there- fore, the AF output level is according to the VOL setting and also the squelch conditions. 4-1-7 SQUELCH CIRCUIT (LOGIC AND RF UNITS) NO

47、ISE SQUELCH The noise squelch circuit cuts out AF signals when no RF signals are received. By detecting noise components in the AF signals, the squelch circuit switches the AF mute switch. A portion of the AF signals from the FM IF IC (RF unit; IC2, pin 9) are applied to the active filter section (I

48、C2, pin 8). The active filter section amplifies and filters noise components. The filtered signals are applied to the noise detector section and output from IC2 (pin 13) as the “SDET” signal. The “SDET” signal from IC2 (pin 13) passes through the noise detector (LOGIC unit; IC1), and is then applied

49、 to the CPU (LOGIC unit; IC11, pin 12) via the “SQL” line. The CPU analyzes the noise condition and outputs the “AMUTE” sig- nal to the AF mute switch (Q37). Even when the squelch id closed, the AF mute switch (Q37) opens at the moment of emitting beep tones. 2nd IF AND DEMODULATOR CIRCUITS Mixer 16 Limiter amp. 3rd IF filter 450 kHz PLL IC IC3 X1 19.2 MHz RSSI IC2 TA31136F 13 2nd IF (19.65 MHz) from Q5 RSSI signal to the CPU pin 7 (Logic unit) 11109 87532 1716 Active filter FI2 Noise detector FM detector