Need a PSU for my towered A1200

[blakespot]

So, I have a towered Amiga 1200 '060 in a 'Noblesse' case that I got from Revanche, LLC.

http://www.flickr.com/photos/blakespot/sets/72157604300573758/

I've had it for 8 years or so, now. A few years back it started going wonky, and I decided that the PSU was failing, so I went and bought another PSU from the local store -- standard PC tower PSU. Well, it lacked this middle-sized power lead that was present on the original tower's power supply, and so I was not able to plug the A1200-to-PC-PSU cable that Revanche threw in into the new power supply. To remedy this, I set out finding the pinout of that missing lead and wiring the Amiga adapter cable into other parts of the new PSU power leads. And it worked...sort of. The machine has been quite touchy ever since, and growing more so.

So. I would like to get a new PC PSU (as I hacked this current one up) and some method of getting that PSU tied into the Amiga 1200. This would, presumably, be an adapter cable that ties to one of the more standard leads coming out of a modern PSU.

Can anyone point me to such an adapter cable for use with a standard ATX power supply or a PSU / adapter combo that will work in my case?

Thanks much.




bp

[som99]

So, I have a towered Amiga 1200 '060 in a 'Noblesse' case that I got from Revanche, LLC.

http://www.flickr.com/photos/blakespot/sets/72157604300573758/

I've had it for 8 years or so, now. A few years back it started going wonky, and I decided that the PSU was failing, so I went and bought another PSU from the local store -- standard PC tower PSU. Well, it lacked this middle-sized power lead that was present on the original tower's power supply, and so I was not able to plug the A1200-to-PC-PSU cable that Revanche threw in into the new power supply. To remedy this, I set out finding the pinout of that missing lead and wiring the Amiga adapter cable into other parts of the new PSU power leads. And it worked...sort of. The machine has been quite touchy ever since, and growing more so.

So. I would like to get a new PC PSU (as I hacked this current one up) and some method of getting that PSU tied into the Amiga 1200. This would, presumably, be an adapter cable that ties to one of the more standard leads coming out of a modern PSU.

Can anyone point me to such an adapter cable for use with a standard ATX power supply or a PSU / adapter combo that will work in my case?

Thanks much.




bp

Just cut and solder your own, it's quite simple.
http://www.ianstedman.co.uk/Amiga/amiga_hacks/Amiga_Power_supplies/body_amiga_power_supplies.html

Most important part is to have a PSU with as low ripple as possible on the 5v line, so I would go with a good brand PSU.

I can recommend the FSP Group FSP400-60APN 400W PSU, it has low ripple values on the 5v line and is a cheep PSU, 13-19mV ripple between 25-100% load on the 5v line is quite good, great value for it's money

[spaceman88]

When I did mine I just used an old PC supply with a power switch and hacked on a 1200 plug, worked great. It was big and ugly and the massive capacitors probably helped with any ripple.

[Lurch]

Don't want to do it yourself? Amigakit has the adapters :-)

[blakespot]

I ordered this. Will salvage the cable segment I have with A1200 PSU adapter on end and wire in.

http://www.ianstedman.co.uk/Amiga/designs/Amiga_ATX_Adaptor/amiga_atx_adaptor.html



bp

[PanterHZ]

I can recommend the FSP Group FSP400-60APN 400W PSU, it has low ripple values on the 5v line and is a cheep PSU, 13-19mV ripple between 25-100% load on the 5v line is quite good, great value for it's money

The problem with this PSU is that it only provides 15A on the 5V rail, which may be a bit low if the Amiga has a floppy drive, harddisk, CD-ROM and other stuff connected.

Personally I use a Antec Basiq BP500U in my towerized A1200, and this PSU can provide up to 30A on the 5V rail. It might seem a bit overkill, but then again I do have a Apollo 1240, Mediator, Voodoo GFX card and various other PCI cards installed there.

[blakespot]

Ok, I have a new PSU and received the A1200 power adapter board to use in wiring the power into the Amiga 1200. Details of the adapter here: http://www.ianstedman.co.uk/downloads/AmigaATXpoweradaptorinstall.pdf

So...I pulled out my digital multimeter to verify the wire colors with the leads on the A1200 plug end, and discovered something odd. There are 5 pins on the Amiga 1200 adapter plug. The plug that came with this A1200 tower has 4 wires coming off of it.

Only two wires are showing continuity from the freshly stripped end to the pin on the A1200 power plug. Just +12v and -12v. No ground, no +5v. Could this be the intended config, or should I conclude that the two other wires coming off the plug have recently become disconnected from the pins inside the rubber housing?

I had been using the Amiga 1200 with that config, plugged into my old ATX PSU with floppy power going into the Amiga 1200 floppy power jack for quite a while, before that PSU died. I am now trying to get running with a new PSU.

Surely a ground should be wired, yes? Is it dangerous to proceed with just +12v and -12v going into the main power connector?





bp