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falter
January 17th, 2014, 01:35 PM
I finally got around to ordering a 'new' power supply from a supposedly working Amiga off ebay. It arrived today, but unfortunately the 1000 still wont' start. You press power, and you see a very thin line at the top of the screen move, then it just sits there up top until you turn it off.

I have replaced every socketed chip except the two beneath the 8520s, using the ones from one of my Amiga 500s. Even the CPU. I also swapped the chips from the 1000 into the A500 where they work perfectly.

I also got a 8361R5 chip off ebay (my agnus is 8361r3)... swapped that.. no dice either.

Any thoughts? I'm at a loss.

falter
January 17th, 2014, 01:37 PM
One other thing -- I don't have a keyboard for this A1000... I'm assuming that isn't required for boot?

barythrin
January 17th, 2014, 02:24 PM
Although it's not necessarily related if you see it go through a few color cycles that can be a normal troubleshooting/posting routine (http://www.nyx.net/~rdavis/AmigaHints2.html). I see another post similar to yours which was a result from a bad battery or battery leakage, you might check around the MB for that. What monitor/device do you have it hooked up to? Have you tried another?

falter
January 17th, 2014, 03:09 PM
Although it's not necessarily related if you see it go through a few color cycles that can be a normal troubleshooting/posting routine (http://www.nyx.net/~rdavis/AmigaHints2.html). I see another post similar to yours which was a result from a bad battery or battery leakage, you might check around the MB for that. What monitor/device do you have it hooked up to? Have you tried another?

There's not really a color cycle.. the screen is all black except for a single, tiny line at the top that bounces briefly when you turn the unit on.

There's no battery either.. so I don't think that is a worry. The monitor is known good. I've actually taken all of the socketed chips I can, put them in an A500 connected to the same monitor, and it comes up ok.

falter
January 18th, 2014, 10:57 AM
I've posted a video here to show what it's doing. I elevated the brightness a bit on the monitor.. it appears that I'm getting a faint grey screen at switch on (you can hear the switch), and then when I turn it off, it's a faint blue screen that hangs around for a random amount of time before going black again. Caps maybe?

http://www.youtube.com/watch?v=sZEp5HP7TTw

KevinO
January 18th, 2014, 01:45 PM
I've posted a video here to show what it's doing. I elevated the brightness a bit on the monitor.. it appears that I'm getting a faint grey screen at switch on (you can hear the switch), and then when I turn it off, it's a faint blue screen that hangs around for a random amount of time before going black again. Caps maybe?

http://www.youtube.com/watch?v=sZEp5HP7TTw

Yeah, that looks like pretty much every dead Amiga. There's nothing special to note about what we're seeing there, except maybe that since there's a raster, the power supply is probably generating at least some of the correct voltage. H

Here's a repair manual to get you started. You will need a voltmeter at the very least, and preferably an oscilloscope.

http://www.bombjack.org/commodore/amiga/amiga-commodore/A1000_Assembly_Level_Repair_314038-01_%281985%29.pdf

falter
January 18th, 2014, 02:50 PM
Yeah, that looks like pretty much every dead Amiga. There's nothing special to note about what we're seeing there, except maybe that since there's a raster, the power supply is probably generating at least some of the correct voltage. H

Here's a repair manual to get you started. You will need a voltmeter at the very least, and preferably an oscilloscope.

http://www.bombjack.org/commodore/amiga/amiga-commodore/A1000_Assembly_Level_Repair_314038-01_%281985%29.pdf

Thanks KevinO.

Manual says 'white bar at top with black screen = agnus'. Maybe my AGNUS is dead, and this R5 chip I got as a replacement just isn't compatible. If I take the AGNUS out and turn the machine on, i get nothing -- no white bar or anything. So it does have some effect.

KevinO
January 18th, 2014, 04:10 PM
Thanks KevinO.

Manual says 'white bar at top with black screen = agnus'. Maybe my AGNUS is dead, and this R5 chip I got as a replacement just isn't compatible. If I take the AGNUS out and turn the machine on, i get nothing -- no white bar or anything. So it does have some effect.

If it's the same part number, it should be compatible. Could be bad, but you shouldn't rule out the power supply. Did you check voltages yet?