In a message dated 7/6/00 12:01:48 AM Eastern Daylight Time, angel@............ writes: << I have some -+ 12 volt supplies I have made for other projects. Where should I make the connections?? Do you suggest cutting and splicing the main power connector that goes to the ATX mother board?? This my first ATX computer and it seems that the power is switch on and off a bit differently than on an AT computer. The power off is just a software thing. -- Best regards, Angel mailto:angel@............ >> Hi Angel, The power supplies I described in my email of 07/05/00 made from radio shack parts are described again below: << Dual plus and minus power supplies (non-switching) are easily made from parts all of which are usually in stock at your local Radio Shack. Buy two 12.6 Volt transformers, two full-wave bridge rectifiers, two 1000 mfd electrolytic capacitors, two 12-volt positive voltage regulators and two 0.1 mfd capacitors. Build two separate 12-volt power supplies and hook them together in series to make a +12V, -12V dual power supply. Where they connect together goes to ground. Radio Shack sells a little book about power supplies which you should also buy if you are not sure how to hook the above stuff together. With the help of the little book anybody can build their own dual power supply for far less than an off-the-shelf dual supply would cost.>> These are two separate power supplies not connected to each other in any way, although they can be side by side on the same circuit board. Their outputs are floating, that is, isolated and not connected together as would be the case if you used one center tapped transformer and a negative voltage regulator. Connect the floating minus output of one power supply to the floating plus output of the other power supply. The point where the two connect together should then be connected to ground or neutral in whatever device they provide power for. The other two outputs provide the plus 12V and minus 12V to power the device. A dual + and - 5V supply can be made from two 6.3 Volt transformers and two plus 5 Volt regulators. The reason for using two transformers and two positive voltage regulators is Radio Shack does not carry negative voltage regulators. The above is a way to make one trip to Radio Shack and come home with everything you need to make a good homemade regulated dual power supply for far less money than you could buy a ready made one. I have never gotten into the guts of my computer so I think I should let someone else explain the details of just how to go about connecting the above dual power supply into your computer. Best regards, Cap __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Larry Cochrane <cochrane@..............>