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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: T3000 on March 18, 2007, 11:24:34 PM

Title: faulty A3000T Power Supply
Post by: T3000 on March 18, 2007, 11:24:34 PM

My A3000T green screen saga continues...
Finally got around to testing the power supply. All the 5 volt leds are reading 12.5 volts. The 12 volt leads are pegging the meter. I would assume this indicates a bad PS.
Now looking to get it repaired. ...and no, I'm not gonna hack in an atx unit...

Title: Re: faulty A3000T Power Supply
Post by: rkauer on March 19, 2007, 12:58:23 AM

But first make sure you have fully charged battery on your multimeter.:-D

Title: Re: faulty A3000T Power Supply
Post by: T3000 on March 19, 2007, 01:36:41 AM

Good point.
Fuzzy multimeter battery contacts = faulty multimeter.

Bought a new digital multimeter, and retested powersupply.

5 volt line reads 5.23v
12 volt line reads 10.54v
-5 volt line reads -4.94v
12 volt line reads 10.54v
-12 volt line reads -9.06v


 

Title: Re: faulty A3000T Power Supply
Post by: da9000 on March 19, 2007, 06:02:44 AM

No wonder you didn't see smoke coming out of the machine (if 5v was showing as 12v)

Either way, my A3000 green screens because of a leaky battery :(  My A500 did because of a burnt (I have no idea how) DRAM chip. Had to unsolder all of them and place sockets and play the game of elimination until I narrowed it down to the faulty one. Pain in the butt, but it worked. Ah, another trick to try  with faulty DRAMs is this: piggy-back chips you know are NOT faulty on top of the soldered DRAMs, until you find a combination (of piggy-backing) that make the machine work, which points to the faulty chip(s)

Either way, good luck to all of us with dead 'migies!