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Service Manual TOP NEXT AD9908187C2 DAB Tuner - ST-GT1000 Colour (K)..Black Type Areas (EB)..Great Britain. (EG)..Europe. 1999 Matsushita Electric Industrial Co., Ltd. All rights reserved. Unauthorized copying and distribution is a violation of law.
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1 Before Repair TOP PREVIOUS NEXT 1. Turn off the power supply. Using a 10 , 10 W resistor, connect both ends of power supply capacitors (C822, C833) in order to discharge the voltage. 2. Before turning the power supply on, after completion of repair, slowly apply the primary voltage by using a power supply voltage controller to make sure that the consumed current at 50 Hz in NO SIGNAL mode should be shown below with respectto supply voltage 230/240 V.
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2 Protection Circuitry TOP PREVIOUS NEXT The protection circuitry may have operated if either of the following conditions is noticed: - No sound is heard when the power is switched ON. - Sound stops during a performance. The functions of this circuitry is to prevent circuitry damage if, for example, the positive and negative speaker connection wires are shorted, or if speaker systems with an impedance less than the indicated rated impedance of this unit are used.
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3 Accessories TOP PREVIOUS NEXT - AC mains lead (EB) area : (RJA0053-2X)......1 pc. (EG) area : (RJA0019-2K)....1 pc. - AM loop antenna (RSA0022-J)..........1 pc. - FM indoor antenna (RSA0007)..........1 pc. - DAB T antenna (RSA0028)..........1 pc. - Stereo phono cable (RJL4P004B08)........1 pc.
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- FM antenna plug adaptor for (EB) area only (SJP9009)..........1 pc. - Remote control transmitter (RAK-STA23WH)........1 pc. - Batteries (R6/LR6, AA, UM-3).........2 pcs. Note: These are available on sales route. TOP PREVIOUS NEXT...
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4 Caution for AC Mains Lead TOP PREVIOUS NEXT TOP PREVIOUS NEXT...
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7 7 7 7 7 Front Panel Controls PTY SELECT (PUSH-SEARCH) PRESET SERVICE- FREQUENCY AM ANNOUNCEMENT SECONDARY SERVICE DATA STEREO AUTO TUNING PUSH OPEN MENU ANNOUNCEMENT MEMORY MEMORY PRIMARY/ TUNING ENTER DISPLAY CANCEL DELETE AUTO MEMORY SECONDARY DATA ATUO/MANUAL 10 11 13 14 15 16 TUNING MODE SERVICE...
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7 7 7 7 7 Equipment Connections Amplifier (not included) TUNER Stereo phono cable (included) This unit AM ANT FM ANT DAB ANT EXT LOOP OPTICAL OUT LINE OUT AC IN AUDIO RDI Optical cables AC mains lead (not included) To household (included) DIGITAL...
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7 7 7 7 7 Antenna Connections The included antennas are sufficient under normal conditions. FM indoor antenna (included) Installing outdoor antennas Fix the other end of the antenna where reception is best. FM outdoor antenna (not included) Adhesive tape Note Disconnect the FM indoor antenna.
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To connect a 300 Ω feeder wire DAB outdoor antenna (not included) Loosen the screws, connect the wires, and tighten the screws to secure the connection. The illustration shows an example of installation. The antenna plug adaptor (included) does not have to be used if the plug on the antenna cable is suitable.
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7 7 7 7 7 DAB and RDS What is DAB? DAB stands for digital audio broadcasting. It is a new form of radio Other features and DAB functions available with this unit that is broadcast digitally. Unlike regular analog broadcasting, digital radio deteriorates less, and is thus able to provide quality sound DAB use digital broadcasting to provide other useful features.
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7 7 7 7 7 Tuning Use to tune to DAB services and FM and AM radio stations. STEREO Preparation: Press [PUSH OPEN] to open the front panel. Press [ /I]. The unit comes on. Press [DAB], [FM], or [AM] to select the band. SECONDARY SERVICE PRIMARY/ SECONDARY...
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7 7 7 7 7 The Display Actual displays depend on the broadcast. You can change the display during reception of DAB and FM RDS broadcasts to view the different types of information. Preset channel numbers are displayed whenever preset tuning is used.
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7 7 7 7 7 DAB Functions Using the announcement function Program the unit to switch automatically to announcements when they start. You are able to choose the variety and language of the announcements. The previous broadcast resumes when the announcement is finished.
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Using announcement services While listening to DAB ANNOUNCEMENT Press and hold [-ANNOUNCEMENT –CANCEL] for about two seconds. The “ANNOUNCEMENT” indicator lights and the unit is ready to receive announcement services. When an announcement service you turned on in the settings steps is received, the unit automatically plays that announcement ( a The “ANNOUNCEMENT”...
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Checking DAB reception quality The function allows you to check reception quality to improve the position of the antenna. While listening to DAB. Press [MENU]. Press [+] three times to display “SIGN. QUAL- ITY”. Change the position of the antenna so the meter lengthens. Press [MENU].
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7 7 7 7 7 Preset Tuning Put DAB services and FM and AM stations into this unit’s preset channels to make tuning simple. There are two methods of preset tuning; auto, where the unit pre- sets all the services and stations it can receive automatically, and; manual, where you can select the services and stations to preset.
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Manual presetting 1 2 1 4 This allows you to preset the services and stations you want in the channels you want. Tune to the broadcast. You cannot preset in DAB if nothing is being received. (“NO SIGNAL” or “NO SERVICE” is displayed.) Press [-MEMORY –AUTO MEMORY].
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7 7 7 7 7 PTY Search with DAB and RDS You can use the PTY signals included in DAB and RDS broadcasts to find particular types of programs. 1 2 1 3 Note PTY search is performed on preset channels. Do the preset- ting procedures before continuing.
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6 Operation Checks and Component Replacement/ Procedures TOP PREVIOUS NEXT...
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7.1 Schematic Diagram Notes TOP PREVIOUS NEXT This schematic diagram may be modified at any time with the development of new technology. Notes: S401: Setting switch (MENU -) S402: Setting switch (MENU+) S403: Memory delete switch (-MEMORY DELETE) S404: Display mode select switch (DISPLAY) S405: Memory switch (-MEMORY—AUTO MEMORY) S406:...
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- < > : DAB - Important safety notice: Components identified by ; mark have special characteristics important for safety. Furthermore, special parts which have purposes of fire-retardant (resistors), high-quality sound (capacitors), low-noise (resistors), etc. are used. When replacing any of components, be sure to use only manufacturers specified parts shown in the parts list.
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SCHEMATIC DIAGRAM 1 Note: The number which noted at the connectors on the schematic diagram as "SCHEMATIC DIAGRAM 1" or "SCHEMATIC DIAGRAM 2" indicates the schematic diagram serial number located on the left corner in the schematic diagram. :FM SIGNAL LINE :AM SIGNAL LINE TUNER CIRCUIT :POSITIVE VOLTAGE LINE...
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SCHEMATIC DIAGRAM 2 :POSITIVE VOLTAGE LINE :FM SIGNAL LINE :AM SIGNAL LINE :AM OSC SIGNAL LINE R104 R109 R106 R108 CF202 470K 470K C105 (0V) 1000P (0V) 3.8V CF201 C104 (0V) (0V) 3.8V 1000P 0.7V 0.7V Q106 UN4111TA Q101 Q102 POWER SUPPLY LINE (FM:ON)
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SCHEMATIC DIAGRAM 3 MAIN CIRCUIT :POSITIVE VOLTAGE LINE R534 R524 B C D C529 C530 R520 R518 R521 R519 R522 R515 R525 (3.3V) 75 74 73 72 71 70 69 68 67 66 65 0.1V R513 3.3V 2.3V 3.3V 3.3V 3.3V 3.3V 3.3V...
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SCHEMATIC DIAGRAM 4 :POSITIVE VOLTAGE LINE :NEGATIVE VOLTAGE LINE :DAB SIGNAL LINE R601 R112A R115A 4.7K R113A C112A 2.7K R111A 4.7K 13.2V 14.8V 1.6V IC601 IC111 TC74HCT7007A NJM318MTE1 INTERFACE OPE AMP C116A 6.3V100 1.6V 1.6V 14.4V C114A R531 IC502 W24258S70LET 256K SRAM R533 3.3V...
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SCHEMATIC DIAGRAM 5 MAIN CIRCUIT :POSITIVE VOLTAGE LINE :NEGATIVE VOLTAGE LINE :DAB SIGNAL LINE A B D C205 R201 330P R606 IC602 R607 TC74HCT7007A R608 3.3V TO 5V CONVERTER R614 (3.3V) (5V) (3.3V) (5V) 3.3V 3.3V 3.3V IC603 TC74HC4050EL 5V TO 3.3V CONVERTER 0.1V 0.1V...
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SCHEMATIC DIAGRAM 6 :POSITIVE VOLTAGE LINE :NEGATIVE VOLTAGE LINE :DAB SIGNAL LINE TP313 TP314 TP315 TP312 R309 TP316 TP311 R307 TP310 R306 R310 0.3V (0V) RAD6 SDAT 1.4V (0V) (0V) 1.6V RAD3 3.3V SCLK 0.3V (0V) 2.8V RAD2 SLRCK 0.3V (0V) (0V) 1.6V...
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SCHEMATIC DIAGRAM 7 :FM SIGNAL LINE :POSITIVE VOLTAGE LINE :AM SIGNAL LINE CONNECTOR CIRCUIT MAIN CIRCUIT :NEGATIVE VOLTAGE LINE :DAB SIGNAL LINE R216 CN203 R932 CN201A CN201B R215 Rch IN TUNER R214 CIRCUIT R213 Lch IN (CN102B) R212 R931 on SCHEMATIC R211 DIAGRAM 2 R210...
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POWER SW P.C.B. W804 1 . . 4 FM ANT TUNER P.C.B. AM ANT 1 ..7 1 . . 4 CN101B CN102B CN401 1 ..7 1 ..7 CN804 W802 W801...
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AM ANT FM ANT Z120 (FM FRONT END) Z101 CF201 RF amp. FM mixer coil coil Q101, Buffer FM IF Local OSC amp. amp. LA1833MN-TLM IC101 FM / AM I F AMP , DET / AM OSC, CF202 MIX / FM MPX +B(FM) Q110 Switch-...
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D401~410 (DAB/FM/AM/SECONDARY SERVICE/DATA/STEREO/ RDS/AUTO TUNING/ ANNOUNCEMENT) 7~15 TP512 Q3~11 BU2090AFE2 VR413 VR414 VR415 (FREQUENCY/ IC402 (PTY SELECT) (PRESET) SERVICE) LED DRIVE S80725SNDNT1 TP513 DATA IC504 X501 TP511 (19.66MHz) Reset 7,29,50, 19~22 68,98,119 MN1021617BA IC501 SYSTEM CONTROL 8,69 TC74HCT7007A TC74HC4050EL IC602 Z401 IC603 3.3V To 5V...
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DAB ANT TP110 IF OUT TP304 TP101 NULL DAB RF NULL TUNER TC74HCT7007A IC601 INTERFACE TP501 Z101 81 80 NDACRST NRST MN1021617BA DABOFF IC501 SYSTEM CONTROL PWROFF 103~111, 3~6, 114~118, 9~12 1~10, 11~13, TP514 TP515 23~26 15~19 A0~14 I/O1~8 CE OE WE AK93C85AM-E1 W24258S70LET IC503...