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Post by ducklite on Jun 18, 2024 22:11:47 GMT -5
Hello , all I bought a Onkyo TX-NR696 off ebay from a listing that stated "does not power on, for parts or repair" when it arrived I was anxious to get to work on it thinking it was something simple like a blown channel or blown fuse but life is never so simple. When I took off the top cover it looked almost new on the inside except for the many dog or cat hairs in it and what seems to be dog or cat vomit on the processor on the HDMI board. corrosion covered most of the components in that area and I thought it would not be recoverable So I cleaned it up and saw that some of the processor pins have been rotted away . Used isopropyl alcohol to clean up the board and removed the main processor chip with my atten hot air gun the solder pads seem to be good. found the processor being sold by mouser so I ordered three when they get here I want to use the programming method I found here to program it and see if it will work again. do any of you guys have a firmware dump for this processor? can upload here or send to me via email. any tips on how to proceed welcomed
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Post by tibimakai on Jun 20, 2024 10:07:28 GMT -5
I haven't heard anybody fixing one of these receivers yet, it is to new. I would try grinding down the plastic, until I would see the leg and solder a wire to it.
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wolek
New Member
Posts: 8
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Post by wolek on Jul 1, 2024 3:01:25 GMT -5
Board after contact with liquid. You won't be able to read the chip, it's secured. If you are from Europe i can fix it.
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Post by ducklite on Jul 1, 2024 18:59:23 GMT -5
I have already ground off the casing and resoldered pins (wires) to the chip I will test it tomorrow and upload a pic of the boardrepair it has two 8 pin EEproms on the underside of the board I have removed them and read them the dump is on my shop computer. Yes main processor chip seems to be a secure chip below it , it has a dram chip seems to be scratchpad memory.
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Post by ducklite on Jul 11, 2024 11:40:35 GMT -5
Well this one did not turn out as planned however I am not giving up on it (this is how we learn). I tested it and it powers up on plugin saying "volume 44" and freezes there none of the inputs can be changed the power button, game, cbl/sat and zone2 don't work I think that a chip on the board is holding up the I2C bus or SPI bus and this is the cause of that freezing. I tested from the buttons to the pin on the MCU ( 144 _KEYINT0) and they all are sending a voltage to the MCU each button is connected to a resistor ladder which divides up the voltage on this pin so each button when pressed sends a different voltage to this pin ( 144_ keyint0).I have bought another receiver from ebay "same 696" that was listed as powers up no sound and fixed it from the one I had the SBL channel had a bad TTA004 transistor in the circuit ( surprisingly it is the only bad component in the receiver).However I still want to fix the first one so maybe I can sell it back and recoup some of my money and at the same time learn a bit about how these things work. I have ordered 2 BD34704KS2 chips some TTA004,TTC004 and some outputs A1492 and the other one C5242 do any of you guys have any ideas on how to fix this your opinions and recommendations are welcomed.
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