MacTester57's HemiMac G4

[MacTester57]

now I have a burned airport express and a burned iMac LCD panel (there are big white rectangles on the LCD).

I'm sorry to hear that. Is the backlight and the inverter still alive? What went wrong? Did you apply 12V to the 3.3v panel supply?

Do you know where could I buy the LCD panel? Is 661-2715 the right number to search for?

It seems, that the number is correct. But don't overpay the LCD. Maybe It's a better idea to buy a complete iMac.

Good luck.

MacTester

 

[imarco88]

I'm sorry to hear that. Is the backlight and the inverter still alive? What went wrong? Did you apply 12V to the 3.3v panel supply?

It seems, that the number is correct. But don't overpay the LCD. Maybe It's a better idea to buy a complete iMac.

Good luck.

MacTester

Yes, backlight and inverter are working, I didn't touch monitor cables.
I really don't know what went wrong... everything worked great (I used the iMac as external monitor for months) but yesterday, before closing the dome to complete the airport express mod (which in testing worked too), the picopsu shut down unexpectedly and I noticed that the airport card was burned.
The really sad part was when I discovered that the LCD panel had some burned part too.

 

[ersterhernd]

I had a short on one of my picopsu's last year, something touched two of leads together and I lost everything on the 3.3v rail, including the BT module and iMac LCD. The inverter was saved only because it wasn't plugged in at the time. Had to replace the pico too. That hurt.

Sorry to hear this.


Ersterhernd

 

[macaddict71]

MacTester,

I have a 1GHz, 17" iMac G4. I have just completed the black and grey LCD cable conversion and then tested the inverter/backlight. However, when I use dremeljunkie's wiring diagram the backlight goes on and off almost immediately. Here's my set up:
1. Using an ATX PSU
2. Faraday cage grounded to wall socket
3. No wires touching the Faraday cage
4. The black/grey LCD connected to DVI connector but not connected to computer
5. The LCD worked perfectly before dismantling it

I tried your inverter cable set up, without the potentiometer for dimming. The green wire is connected to the +3.3VDC ATX. Again, the backlight goes on then off immediately. Disconnecting the red wire and then re-attaching produces the same result.
I note in your post #5 that you too had the same result using dremeljunkie's wiring set up.

Any advice you can provide would be most appreciated.

macaddict

 

[MacTester57]

Hi macaddict71

Welcome to the community.

Again, the backlight goes on then off immediately

I had the same issue during the first backlight tests. The problem were the used alligator clamps. The different voltage levels were not stable enough and this caused the backlights to shut off immediately after start.

I've sorted out this issue using massive screw terminal blocks instead of the alligator clamps. Particularly the GND wires are very critical, because they are the "0 Volt reference level" for all your devices.

Good luck!

MacTester

BTW: we want to see pics!

 

[macaddict71]

MacTester,

You're brilliant!
Turns out my alligator clips were the culprit.

I'll post pics once I get a little further into the build.

Thanks,
macaddict71

 

[MacTester57]

Turns out my alligator clips were the culprit.

Good to hear, that you've sorted out this issue.

All my hacks are now updated to 10.9.5 and work flawless. Here you can see both the G4 Cube and the Hemi sitting on my main desk:

And BTW: it was a pleasure to have ersterhernd here for a visit today!

Happy hacking
MacTester

 

[apple524]

It's good job!

 

[ersterhernd]

And BTW: it was a pleasure to have ersterhernd here for a visit today!

MacTester

It was a highlight of our trip to Europe, Mactester!

Thanks again so much for your hospitality.


Cheers!


Ersterhernd

 

[MacTester57]

It's good job!

Thanks

It was a highlight of our trip to Europe, Mactester!

Thanks again so much for your hospitality.


Cheers!


Ersterhernd

You're welcome! Enjoy the rest of your Europe trip.

Gruss
MacTester