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There are currently no product reviews.
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Great PDF easy to read good info needed for replacment of belts and assembly and specs.
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complete and unabridged very good quality
easy to download.
recieved in two days.
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Awesome manual. Complete diagrams of all board assemblies as well as how to get to each part of the t.v. down to the individual screws and their locations. Get it.
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perfect copy, im very satisfied, i was need the diagram over the powersupply and
the copy was very sharp
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This is exactly the service manual I needed.
Complete with all schematics, partslists, PCB layouts and alignment instructions.
This manual covers both the T-4970 en T-488F Onkyo tuner.
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Freeze (2/2)
Sites
MAIN Assy
Waveforms
MAIN Assy
71
Points to be checked
� Check the waveform at the CPU16M Test Land, referring to the waveform photo, to confirm that the crystal oscillation circuit is operating normally.
Causes & Measures to be taken
An unstable waveform or extremely low level suggests chip fracture or partial damage of the crystal oscillator (X301). Replace the chip or X301.
Remarks
A
MAIN Assy
MAIN Assy
19
MAIN Assy
MAIN Assy 23 to 30
ç Check the waveform at the designated point on the An unstable waveform suggests loose connection of PRGM line, to confirm that the MPU (IC301) resets the output terminal of the MPU (IC301) or chip the FPGA (IC302) properly. fracture on the PRGM line. Even if the waveform at the designated point is � Check the waveform at the point designated on the An unstable waveform suggests loose connection of waveform photo, to confirm that the configuration the output terminal or chip fracture. procedures between the MPU (IC301) and FPGA Even if the waveform at the designated point is (IC302) are properly performed. normal, there may be poor contact of connectors in downstream lines. Resolder the output connectors,
Display (1/2)
Sites Waveforms Points to be checked Causes & Measures to be taken Remarks
Lighting of the LEDs and indications and the FL display on the control panel do not function. If the power supply is normal, this symptom is caused by a defective DISPLAY MPU (IC501,) which controls the display on the control panel, including the FL indication and lighting of the LEDs. (If the DISPLAY MPU is normal, the indications of internal data on the DISPLAY MPU, such as POWERON and E-8709, will be displayed on the DATA-FL display.) To confirm that the core block of the MAIN Assy is normal, play back a CD without using the control panel and check the audio output. DFLB Assy SECB Assy REGB Assy TRNS Assy ACIN Assy z Check the power to be supplied to the control panel, paying attention to the following points: (1) Is the ICP damaged?, and (2) Are cables firmly connected? x If power is not supplied to any power system, check the primary source. Inappropriate commercial power input or blown primary fuse (FU8001) or glass fuse (T21) are possible. DFLB Assy
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B
Replace the ICP or check the cable connections.
Replace the fuses.
C
Abnormal delay time or an unstable waveform suggests fracture of the C507 chip. Replace the C507. If the symptom is not ameliorated, replace the IC502. An unstable waveform or extremely low level suggests chip fracture or partial damage of the crystal oscillator (X501). Replace the chip or X501.
DFLB Assy
c Check the waveform of the XRST line, referring to the waveform photo, to confirm that the Reset IC (IC502) resets the DISPLAY MPU (IC501) properly. The Reset IC is normal if resetting is canceled about 70 msec after the power is turned on. v Check the waveform at Pin 12 of IC501, referring to the waveform photo, to confirm that the crystal oscillation circuit is operating normally.
DFLB Assy
DFLB Assy
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No indication only on the DATA-FL display If the power supply is normal, this symptom can be caused only by a failure in the DATA-FL (V501) or the communication between the DATA-FL and DISPLAY MPU (IC501). z Enter Display Check mode of Service mode and If the LEDs and JOG-FL (V601) do not light, nor does check if other keys on the control panel function and if the DATA-FL (V501) display, the DISPLAY MPU that the LEDs light. controls those will not function properly. See "Lighting ACIN Assy DFLB Assy SECB Assy TRNS Assy DFLB Assy DFLB Assy
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D
x Check the setting of the voltage selector switch (on Set the switch to the position that corresponds to the the rear panel). (for RLF model) commercial power source. c Check the Vload voltage (VLD, VLDD). If the voltage measured at the periphery of the power terminal of the DATA-FL (V501) is 29.3 V DC or more, it is OK. v Check the FLAC voltage (FLAC1, FLAC2). If the voltage measured at the both ends of the DATA-FL (V501) lead is 4 V AC or more, it is OK. If the voltage is 0 V, the ICPs (IC25, IC58, and IC59) are fried. Replace the ICPs.
If the AC current waveform does not appear, check the connection between the Assys.
DFLB Assy
b Check the waveform at Pin 46 of DATA-FL (V501), If the 5 V power is not supplied, soldering touchup is to confirm that 5 V power is supplied to the built-in needed. driver. DFLB Assy 54 to 57 n Check the points designated in the waveform photo to confirm that the procedures of the communication between the DISPLAY MPU (IC501) and the DATA-FL (V501) are normal. A solder fracture of the DATA-FL terminal or loose connection of the terminals on the communication line between the DISPLAY MPU and the DATA-FL is suspected. Soldering touchup is needed. If the symptom is not ameliorated after soldering touchup, replace the DATA-FL.
E
DFLB Assy
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CDJ-800MK2
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