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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: falter on October 28, 2015, 05:05:54 AM
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Hi guys,
Took out my dead Amiga 1000 again and tried some more tricks. I purchased two more Agnus chips, another power supply and tried moving things around. I've now swapped all the socketed chips with known good, psu, the whole 9 yards, and all I get when I flick on the power is a solid power LED, and a thin grey and blue line up at the top of the monitor.
Looking for any suggestions on where else to look with this unit. It's a Rev A board. I'm kind of getting suspicious of the WCS daughterboard, or maybe RAM?
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Any click from the floppy drive? Anything on the composite output?
I noticed you had another thread in a different forum, someone was suggesting test the voltages from the PSU, did you ever confirm that?
I'd suspect the daughterboard too, but aside from swapping with another not sure what the process is to test it. Clean connectors and reseat?
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Hi guys,
Took out my dead Amiga 1000 again and tried some more tricks. I purchased two more Agnus chips, another power supply and tried moving things around. I've now swapped all the socketed chips with known good, psu, the whole 9 yards, and all I get when I flick on the power is a solid power LED, and a thin grey and blue line up at the top of the monitor.
Looking for any suggestions on where else to look with this unit. It's a Rev A board. I'm kind of getting suspicious of the WCS daughterboard, or maybe RAM?
Do you have a different monitor that you could try?
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@ falter
had a few black screens on my A1K and they both were due to the 68k CPU, one time it was just faulty and the other time it just needed to be reseated as one of those darn weak legs was bent and not making contact
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I did test both power supplies and voltages came in where they should have been. The composite video output is slightly different, when you turn the computer on there's a switch from black to a lesser black. Then you switch it off and there's a 1-2 second flash of white, then nothing.
There's no clicking from the floppy drive at all. Before it would spin endlessly but now it does nothing.
I'm 99% sure I've addressed everything with the 68k CPU.. I've tried four of them, all known good, I've seated them well, checked pins, checked continuity from pin leg to solder point underneath.. all comes up good. And the CPU gets warm.
I highly doubt at this point it's a chip issue, unless I got three bad Agnus' in a row, but I doubt that. So the daughterboard seems to be a next suspect. I've heard of RAM causing issues on post but not complete blackout like this.
Is there anything special/collectible about the Rev A boards? ie. is it worth going to extraordinary efforts to save them? Or would I be better to just buy one of those Rev 6 boards on ebay? Assuming of course it's not the daughterboard. I can't remember if the Rev 6 got rid of the WCS.
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Neither of the NTSC boards ditched the WCS (unlike the PAL mobo). I may have a rev 6 and an A still if you'd like to purchase a known good and fully working board set. Not sure what the difference is between the two, other than A having copper traces and 6 having silver/tin. Was about to list one or both soon on eBay anyway. Can also sell with IC's removed if you want to save a few bucks. PM if interested and in the States!
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roms suffer from bitrot maybe? this has happened to a cdtv i had. also could be a bad pal chip.
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If you run completely out of other ideas, you could always try baking the board in the oven to reflow all the solder points. :lol:
(yes, I know this is pretty much a last-ditch option, haha)
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Did you check the capacitors near the video out for leakage?