Madaracs
Well-known member
Hi guys,
I have a Defender that has a Happ Switching Power Supply in it.
I bought it non-working. The previous owner shipped off the RAM/CPU board to Eldorado and it's been there for 6 months or something at this point I'm not ever expecting to see it.
In the meantime I bought a lot on ebay of some Defender boards: 3 ROM boards and 4 RAM/CPU boards. I've been attempting to get them up and running. All were shipped "as is" to me and I expected them to not work.
The rest of my Defender boards are all present so I decided to upgrade the RAM on the two complete RAM CPU boards and do this suggested mod:
http://www.scoresaves.com/misc/JustSayNoTo4116.html
I'm not sure how Defender is supposed to be wired up with the switching power supply in, so I just plugged in everything I could find and fired it up.
Nothing, nada, zilch. Just a high pitched wine, the four LEDs lit up solid on the ROM board and nothing happens.
Is there a basic troubleshooting guide someone could point me at so I know where to test voltages and stuff?
I've also been reading that I should recrimp the interconnect cables as well?
I would LOVE to be able to ship my CPU/RAM boards to someone to see if they could get them to work in their machine if anyone would be willing to help me out here?
I have a Defender that has a Happ Switching Power Supply in it.
I bought it non-working. The previous owner shipped off the RAM/CPU board to Eldorado and it's been there for 6 months or something at this point I'm not ever expecting to see it.
In the meantime I bought a lot on ebay of some Defender boards: 3 ROM boards and 4 RAM/CPU boards. I've been attempting to get them up and running. All were shipped "as is" to me and I expected them to not work.
The rest of my Defender boards are all present so I decided to upgrade the RAM on the two complete RAM CPU boards and do this suggested mod:
http://www.scoresaves.com/misc/JustSayNoTo4116.html
I'm not sure how Defender is supposed to be wired up with the switching power supply in, so I just plugged in everything I could find and fired it up.
Nothing, nada, zilch. Just a high pitched wine, the four LEDs lit up solid on the ROM board and nothing happens.
Is there a basic troubleshooting guide someone could point me at so I know where to test voltages and stuff?
I've also been reading that I should recrimp the interconnect cables as well?
I would LOVE to be able to ship my CPU/RAM boards to someone to see if they could get them to work in their machine if anyone would be willing to help me out here?
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