I just recently put back together a Sony MZ-1 Walkman because it wasn't accepting or rejecting the minidisk, and now the Hold Switch doesn't work. Any ideas to why this is happening?

Thanks,

T

Power cycling will flash green/OnLine for ~20 blinks, switches to On Battery, then blink "On Line" a few more times, then switch OnLine off, and continue beeping.

Doing the 10s power button hold to enter power-sensitivity-adjustment mode, and trying the 1/2/3 power sensitivity levels didn't seem to help.

I saw a schematic at https://www.eevblog.com/forum/repair/apc...

Apc 640 0253e Rev05sch 124

⟐ Edited by author August 18, 2026 at 17:25 MST

The problem is, the console has no power. Doesn't respond to power button, eject button, stays off. PSU led is always orange. Here are the things i found: 1.8V standby is okay, 3.3V is okay too, at the power plug from pin 1-3 there is 0V, from pin4-7 there's 0.2V, that grows to 0.3V if plugged in, SMC_RESET_N at J2B1 PIN 6 is always low, no matter what, its at 0V. I tried to power it with my lab psu so i could find whether there's a short (thats potentially feeding back to the power connectors) but nothing. Still no life. The 3.3V is there at the RF Board so that's not the problem, the RF board also work on another motherboard. Already tried to reflow the NAND, Southbridge, and ANA to no success yet. Any ideas what could cause this? I'd appreciate any help! Thanks for reading!

EDIT: Forgot to mention, that i measured connectivity between J2B1 Pin 6, and all the points that are mentioned being connected to SMC_RESET_N, and all seems fine.

Pictures of no POST board:

Pictures of board that POSTS:

⟐ Commented August 18, 2026 at 15:12 MST

Symptoms:

• Mac does absolutely nothing when pressing the power button.
• Tried both USB-C ports.
• Internal white LED stays solidly on when the charger is connected.
• Battery has been tested both connected and disconnected.
• The Mac can be put into DFU mode and is detected by Apple Configurator on another Mac.
• Both Revive and Restore fail at step 4/4, around 50%, with:

• gave up waiting for device transition from dfu state to dfu state

• and/or:

• Probably forced into DFU mode externally

• This happens with both Revive and Restore.
• Cable might be not good, I'm going to retry with an official Apple cable suited for a Revive/Restore purpose soon.
• The Mac have been dropped, so physical motherboard damage is possible.

With the Mac powered off, charger connected, battery connected, I measured:

PPBUS_G3H = 12.63V
PP3V3_G3H = 3.30V
PP5V_G3S = 5.11V
PP1V8_G3S = 1.80V
PP0V9_SSD = 0.90V

PP1V8_SSD = 1.80v

PP3v3_S5 to ground = 780 ohms

F3000 & F3001 = 19.94V on each side of the components

C7050 & C7056 = 12.63V

Main rails appears to be good, so I'm wondering what could have gone wrong.

If anyone has an idea,

Best regards,

Another official Apple cable did not fix the problem

Could it be the SSD?

⟐ Edited by author August 18, 2026 at 14:04 MST

⟐ Commented August 18, 2026 at 14:01 MST

⟐ Commented August 18, 2026 at 12:45 MST

⟐ Commented August 18, 2026 at 10:26 MST

⟐ Commented August 18, 2026 at 10:22 MST

Arabic->English translation:

Title: How to install the cylinder head gasket

Description: The component that separates the coolant and the oil inside the engine.

⟐ Commented August 18, 2026 at 9:51 MST

Haw a solve

⟐ Commented August 18, 2026 at 9:39 MST

⟐ Edited August 18, 2026 at 9:36 MST

Induction cooktop touch controls not responding

The induction cooktop turns on and operates, but some touch controls are not responding?

⟐ Commented August 18, 2026 at 8:35 MST

Body: I am trying to flash a custom Allwinner H618 Android TV box / embedded board (Model: BA882_141_V1.0 22244) from a defunct manufacturer, and I don't have the original backup firmware.

Details:

• SoC: Allwinner H618
• RAM Chips: 4x 4EE77 D9QBQ (batch codes vary slightly: HFB7, H8JP, HHTC)
• Symptom: Every compatible firmware I've tried stops flashing at around 44%–45% and throws error 0x161 (Download Boot Failed). The front display doesn't light up, and only the optical port LED stays on.
• What I've tried: Tested multiple generic firmwares matching the hardware, but they all fail at the bootloader/DRAM initialization stage due to missing custom boot parameters.

Is there a known workaround, or a way to build/modify a compatible bootloader or DRAM configuration to bypass this error without the original factory firmware?

⟐ Commented August 18, 2026 at 7:29 MST