How to mod a PC PSU for radio?

[Singularity35]

Need your help again guys. I heard that you can mod a PC psu to get 13.8v and over 20 amps from it. Enough for a mobile/base. Is this true? And if it is, can you point me out to any resource that can help me do it? Thanks in advance.

 

[tba02]

It depends on the power supply. I have a few that run 12.7 volts, 17 amps. I never felt a need to change them. All of mine are desktop PSU's (jump the green wire to ground - black)

Did you have a specific one in mind? Desktop PSU's and server PSU's differ.

 

[Singularity35]

It depends on the power supply. I have a few that run 12.7 volts, 17 amps. I never felt a need to change them. All of mine are desktop PSU's (jump the green wire to ground - black)

Did you have a specific one in mind? Desktop PSU's and server PSU's differ.

We have a lot of low cost, generic PC PSU's here. A lot of people use them for their mobile/base but they can't go high power since the 12 volt wire gives about 5-6 amps. It's the 5 volt rail that goes to maybe 25 amps.

 

[SLR_65]

I just did this. On the motherboard connector the green wire is jumpered to any black wire to turn the unit on. It may fire up and then shut down as some units need to see a load to keep running. Most units also need a load to regulate properly. My unit would stay running but had about 11.5v with no load. I put a 10 ohm, 10 watt resistor between 5v and ground and then it came up to 13.4 v and seems to stay there no matter what other load I put on it. I only have a 30 watt soldering iron and the 3.3, 5 and 12v wires are all soldered in bunches, so I couldn't remove the un-needed ones, so I just cut them and taped them off. I fed a positive / negative binding post with two 12v and two gnd wires. The 10 ohm, 10 watt resistor may get hot so I wanted it solidly mounted in a well ventilated spot. I took one lead and wrapped it around the pcb mount screw and stood the resistor straight up in the corner by the vent holes right in line with the vent fan, then hooked the other end to a 5v lead. Works fine and the resistors stands straight up in good air flow. The resistors are cheap on fleaBay from Radio Shack, around a buck and a half for two delivered if I recall correctly. I have an extra, if you need one pm me and I'll send it to you. So far, it works fine.