Computer PS for multiple radios?

[LordJ]

Hey all, I have a brand new 450w 10A psu for a pentium comp but no need for it as I have a better one for my computer. Question is, anyone use this type of PSU for running their radios? Any interference problems or the like? I was thinking about getting a rig runner until I rememebered I had this unit laying around.

 

[Thayne]

Most computer power supplies interface to the motherboard, so unless you know the protocol used to tell the power supply that everything is ok, I don't think it would work.

Also since they are switching type power supplies, in the case of a malfunction in it it could possibly fry whatever was connected to it, of course thats possible with a lot of electronics!

 

[Dubbin]

Most computer power supplies interface to the motherboard, so unless you know the protocol used to tell the power supply that everything is ok, I don't think it would work.

It would work just fine. All it takes is to jump a couple of wires to turn it on.

 

[Thayne]

Which two??

 

[Dubbin]

Which two??

If I remember right (and I think I do) it is the green wire to any of the black wires. Some times you also need to jump the grey wire to a ground.

 

[crayon]

Also since they are switching type power supplies, in the case of a malfunction in it it could possibly fry whatever was connected to it, of course thats possible with a lot of electronics!

What? If anything malfunctions it could fry electronic gear. The big difference between a regular power supply and a computer "switching" power supply is that the switching only uses the power it needs. This is a non-warning.

If I remember right (and I think I do) it is the green wire to any of the black wires.

aye. The green wire would be pin 14.

http://www.pcguide.com/ref/power/sup/partsMotherboard-c.html

 

[Dubbin]

aye. The green wire would be pin 14.

I know that and you know that but maybe he didnt know that. Thats why I used colors.

 

[John_M]

The RigRunner would be easier. You could use the Computer power supply though. Get the Rigrunner if you have the money.

 

[Thayne]

Since Crayon's reply, I thought of another reason I wouldn't do it--since it is a switching power supply the output has somewhat of a direct connection to the incoming line voltage of which of course one side is grounded. Because there is no transformer to isolate the output of the switching power supply even though it is only supplying 5 or 12 volts DC output, there "may" be a higher potential to earth ground.

(Look inside one and see how crappy they are constructed)

This is not a problem in a computer with a "hopefully" grounded case, but it might be for powering a handheld scanner without a grounding connection; or it could really be bad for the scanner if the antenna shield is grounded.

Besides, computer power supplies are UL listed to power PC's, not scanners-- :idea: 8)

 

[Voyager]

Also since they are switching type power supplies, in the case of a malfunction in it it could possibly fry whatever was connected to it, of course thats possible with a lot of electronics!

Is that why I've seen so many power supplies go bad and the motherboard and everything else comes back fine when the power supply is replaced? (IOW: Nothing in the PC is fried)

I've seen more things fry when the regulator goes out on a 'brute force' power supply (the type other than switching) than a switching supply. But then, I've seen many more brute force supplies compared to switching supplies, too.

Just beware what you connect to - one wire is 12V (the YELLOW wire) while the other is 5V (the RED wire). I would leave the AT/ATX connector alone and just use the drive power wires (the ones with just red, yellow, and usually two blacks). The black wires are ground, BTW.

The RigRunner is a good idea, too. That will provide fused power for everything.

Joe M.

 

[flyingwolf]

And Red and Yellow are 7 volts +.

It would be possible. But it is easy? Well yea. Is it Smart? Thats up to you. Use Fuses. Build a nice setup and you should be good to go.

 

[crayon]

Use Fuses.

o yeah.

Build a nice setup and you should be good to go.

aye. Rigging up from spare parts is half the fun of electronics! (at least for me)

 

[VegasCorbin]

Since Crayon's reply, I thought of another reason I wouldn't do it--since it is a switching power supply the output has somewhat of a direct connection to the incoming line voltage of which of course one side is grounded. Because there is no transformer to isolate the output of the switching power supply even though it is only supplying 5 or 12 volts DC output, there "may" be a higher potential to earth ground.

(Look inside one and see how crappy they are constructed)

This is not a problem in a computer with a "hopefully" grounded case, but it might be for powering a handheld scanner without a grounding connection; or it could really be bad for the scanner if the antenna shield is grounded.

Besides, computer power supplies are UL listed to power PC's, not scanners-- :idea: 8)

Not all power supplies are created equal!

I use a number of PC supplies in my work and some are isolated from Line (or earth) ground and others are tied to the AC (Earth )ground. I have used both with out problem. To find out, just connect a Ohm meter from any Black wire to the ground pin on the AC Cord. (With the unit unpluged of course )

One thing to note though. PC supplies put out 12 volts and NOT the 13.5 volts your typical car puts out. Most scanners will work fine but if yours is more sensitive it may be an issue.

Just my thoughts

 

[Voyager]

One thing to note though. PC supplies put out 12 volts and NOT the 13.5 volts your typical car puts out. Most scanners will work fine but if yours is more sensitive it may be an issue.

Test the voltage when the car isn't running, or after it's sat for a while powering something. 12V isn't going to make any difference. I've seen cars put out much more than 13.6V, too. In a way, the PC PS may be more safe.

Joe M.

 

[Dubbin]

NOT the 13.5 volts your typical car puts out.

Make that 14.5 volts. Most car batteries will fail if its much below that.

 

[kb2vxa]

Hi guys,

"If I remember right (and I think I do) it is the green wire to any of the black wires. Some times you also need to jump the grey wire to a ground."

FFFZZZAAAPPP!!!

Rule of thumb, when in doubt, don't. Even if you get it to switch on you still have multivoltage outputs to consider, uh, 12V+ is the red and black, uh, negative, I think. Actually that output hasn't much "oomph" since it's meant only to power a fan or two, a 500W supply may put out only 1W at 12V, the rest being for memory and logic.

The best bet is ask yourself why the power supply in the first place and do I really need one? If after much deliberation the answer is "yes" then go for a regulated supply with sufficient amps output to power everything comfortably, then double the amps. Why? So the supply doesn't strain, that's why. I have a 60A supply running 3 ham rigs and still I only transmit one at a time and eventually it gets rather hot. The average 18 year old kid can carry a 100lb sack but a strong man can go the distance with it.

 

[pro92b]

a 500W supply may put out only 1W at 12V, the rest being for memory and logic.

The supply in my computer, rated much less than 500W, has a 6 amp 12 volt output (11 amp surge rating). 12V is used for motors in hard drives, CD/DVD drives, floppy drives, fans, and some PCI cards use it too. Not that I advocate using a PC supply for radio, but the 12 volt output generally has a good bit of output current capability.

 

[crayon]

Rule of thumb, when in doubt, don't.

This is non-useful advice. When in doubt, a person *should* educate themselves with facts in order to make a proper decision. Nothing is ever learned by running away from a challenge.

500W supply may put out only 1W at 12V, the rest being for memory and logic.

huh?? :roll: more non-advice here ..

The sticker on the PS should show what it is rated for. Taking a quick look at the computer open on my bench here shows:
+12v @ 6A
+5v @ 22A
+3.3v @ 14A
-5v @ 0.3A
-12v @ 0.3A

 

[Dubbin]

Hi guys,

"If I remember right (and I think I do) it is the green wire to any of the black wires. Some times you also need to jump the grey wire to a ground."

FFFZZZAAAPPP!!!

Those ARE the correct wires so NO there would be NO "FFFZZZAAAPPP" You should find out the facts about things before you give advice or try to correct someone when they are right in the first place.

 

[Caesar]

hehe, keep us posted on how this works out, i might try it myself on something old that i will nto worry about frying, but ofcourse have the fuses in place to help me out!!!