Can any of you guys give me some input on finding a +/-9V power supply?

I know there are some technologically saavy EE guys out there...can anybody build me a switching power supply with +/-5V & +/-9V with 1A max. Please give me a quote.

Thanks!

2/8/2006 2:43:06 PM

get a computer power supply and use the red lines... and go to sams and get the 24 pack of 9v batteries... or make a resister devider for the 12v (yellow) line of the power supply

problem solved


(mostly sarcasm but those methods would in fact work... )

2/8/2006 4:06:45 PM

It might..but it will have to work for atleast 2 months without maintenance
And that is the reason asking for some knowledgable person to help me with building it and not your goFigure sarcasm

2/8/2006 5:49:58 PM

Ok, here's a basic dc powersupply that yields 3.3v, 5v, and 12v...so here goes.

You can use a regular switching power supply from an old computer for this. Usually the older the power supply, the more amps it will have. This is what you really want to look for. The more amps the better.

Step 1: Open the cover of the Power Supply
Step 2: Cut all connectors off the groups of wires
Step 3: Discharge the capacitors by touching a black wire to a red wire
Step 4: Separate all the different color wires into groups
Step 5: GROUND the green wire to the casing or a black wire. (This is your on switch...you can put a switch on this if you like)
Step 3: Cut a Red wire for your +5v, Yellow wire for +12v, Orange is +3.3v if you want it, Black wires are your ground.
Step 4: Put come kind of connector posts on the box if you want to get fancy
Step 5: Put the case back together, connecting the wires to their respective posts.
Step 6: Profit


I used a few of these power supplies for about a year a piece and they worked just fine. If you have any more questions, just ask. There are also ways to step down the 12v to 9v...

[Edited on February 8, 2006 at 6:41 PM. Reason : .]

2/8/2006 6:39:26 PM

or go find a 12+ volt transformer (something from a laptop / LCD would work great) and go to radio shack and buy a LM7805 and LM7809 , they will do exactly what you need and probably have caps drawn on the box.

if you cant figure that out, then use a power supply.

ps they arnt the most efficient devices so you might need to heatsink them.


expanding on what gofigure said you could maybe balance between the 3.3 and 12 volt rails and net a near 9 volt potential difference. good luck on that

[Edited on February 8, 2006 at 6:44 PM. Reason : .]

[Edited on February 8, 2006 at 6:44 PM. Reason : .]

2/8/2006 6:43:15 PM