Will salvaged computer parts work? Even after in the rain?

I salvaged a coputer from the trash today as a way to teach my self some soldering techniques when I noticed the fan inside. The fan is ideal for implementing into my telescope but when I dissambled the power supply and extracted the fan it didn't seem to work even after hooking it up to a 9v battery. Also the small pieces of the computer on the motherboard, can they be used even if they may have gotten wet? This would save me some cash if i could just desolder them and use them for later projects. I don't know the names of these but they are the cylinder, and the flat circular parts that solder into the board.

Reply to
rdeol85
Loading thread data ...

In data Sat, 17 Jun 2006 07:09:34 +0200, ha scritto:

9V battery .. uhm... you need a 12 VOlt power supply!

electrolytic capacitors?

>
--
Inty.Evolution
intiglietta@email.it -> per email normali e con immagini Jpeg
Reply to
Inty XP

Computer motherboards are pretty hard to solder / unsolder. Multiple layers and lots of heat dissipation suck the life out of most irons.

The fan may have a series diode inside - did you try the battery using each polarity? By that I mean did you try reversing the wires when it failed to run?

Mark Z.

Reply to
Mark D. Zacharias

snipped-for-privacy@gmail.com ha escrito:

you can dry the board with a low temp hairdryer and many things may be salvageable if you don't leave it damp sitting around. i think you need to read up on the basic terminology and find out what each component does. look on google for electonics basics sites, i think you'd get a lot of useful info out of doing this which would help your future projects

-B.

Reply to
b

Reply to
Papa_J

IME 12V computer fans will start and run quite happily on 9V, so a 9V battery should be fine for testing purposes.

Dave

Reply to
Dave D

In data Sat, 17 Jun 2006 20:38:00 +0200, Dave D ha scritto:

Ehr... a 12 V fan runs fine with 7 Volt (12 and 5 Volt wires)

--
Inty.Evolution
intiglietta@email.it -> per email normali e con immagini Jpeg
Reply to
Inty XP

But 9 volt batteries die in droves, so the OP should make sure his battery is at least "OK".

Mark Z.

Reply to
Mark D. Zacharias

Hi I've salvaged many PC's and moniters from the curb. Recently I got an IBM PC and 21'' moniter that was out in the rain I took the covers off of both neither had got wet, sometimes the outside of an item can be soaked and the inside be dry. As far as wet stuff I just take the covers off and let them air out for a few days or use a hair dryer on Low if you have the patience. I think a PC board would be an awful thing to pratice solidering on with the multi layers. But if you are already good at solidering and want to experiment on multi layer boards I guess it would be a free source of boards to practice on. P.S. most of the PC's I've found by the curb work fine most in need of a reformat.

Regards, Chance

Reply to
Chance

Yes, they do usually, so why point out that the fan wasn't working because it needed a 12V supply?

12 and 5 Volt wires? 7 Volts?

If you're saying you've connected a 12V fan between the 12V and 5V wires to test it on the difference voltage of 7V and it worked, well yes, I'm not surprised- I've had them start and run (slowly) as low as 4.5V, but you're the one who said implied the fan wasn't working because it needed 12V, so I fail to see your point.

Dave

Reply to
Dave D

Just a long shot, maybe the fan doesn't work. I don't think they die all that often but it has to be a possibilty.

Also I wouldn't bother trying to scrounge parts from a motherboard. Spread the word around to all your friends, neighbours and family NOT to throw away any old(broken or unwanted) electrical goods and start soldering/unsoldering. You might be able to fix some of it. I've gotten plenty of gear that way. Most doesn't work but so what. Someone mentioned finding out what the parts are and do to learn more.

Can't afford books, go to your local library.

Good luck, Boozo.

Reply to
Boozo

Water shouldn't hurt them.

If you don't know what the parts are though, how do you expect to use them for anything?

Reply to
James Sweet

In data Sun, 18 Jun 2006 01:53:23 +0200, Dave D ha scritto:

It will not work with a 9 Volt battery!!! because it's capable of only

150mA ...! (i'm not so good in english)
Reply to
Inty XP

I've seen water damage glass diodes, 1SS1555, 1SS2076, etc. Seems the seal sometimes isn't perfect where the lead goes into the body of the diode. A bit of corrosion apparently sets in, and a few days or weeks later the diode goes intermittent or just open-circuit. Fixed a Sony receiver with protection problems where this had happened. Replaced the bad diode, unit was fine, then a week or so later another in the general area failed the same way. The circuit board had a small water stain in the area.

Mark Z.

Reply to
Mark D. Zacharias

That's not true! You appear to be confusing the battery's milliamp-hour rating with its maximum output current! A battery's mA/H rating (not milliamp rating!) is how much current it can supply for one hour, not its maximum current capability. A 9V battery (or 8.4V NiCad/NiMH rechargeable) can supply far more current than its mA/H rating for short periods.

For example, a decent 150mA/H 9V battery will supply 300mA for (approx) 30 minutes, and certainly enough to test a computer fan, which are often less than 200mA anyway.

Dave

Reply to
Dave D

Reply to
Fred

If I attached the fan to the tube of the telescope (a newtonian scope) I can push the hot air out of the tube and bring the air temperature to the same as it is outside. Thus limiting the amount of "heat ripples" seen through the eyepiece. Its a real pain to deal with when using large newtonians, and can largely limit a nights observing. I have tried the 9V battery on both polarities and nothing works. I may have to accept that this item was junk when I picked it up. One indication should have been that the case had no cover, meaning that someone probably tried to salvage it and failed. Is there any way to disassemble the fan so I can take a deeper look at the parts? I tried pulling the actual fan from its housing to expose the circuits but the frame of the housing started to crack. It's not that big of a deal if I

*have* to break the hous> So I look at this from another angle, Maybe the power supply failed and
Reply to
rdeol85

There's usually a label on the fan housing- under that there should be the end of the shaft with a clip or nylon circlip on it. Remove that and the fan rotor should come away from the housing. I don't know why you're wasting your time though, there's very little in them and they generally aren't worth repairing. Sometimes lubricating them can give them a new lease of life, but electronic repairs on fans are impractical in most cases.

Dave

Reply to
Dave D

snipped-for-privacy@gmail.com ha escrito:

thats because it needs 12v- i have had that situation, 9v simply won't do for some units.

-B

Reply to
b

I can see why it sounds strange to go throuhg all of this, but at my local electronics store (rural Iowa, not much selection) has fans starting from $20. The same fans are $6 on the net so instead of buy one or the other I though I would give a repair a try. This is less than my tenth attempt at working with electronics and the idea to have satisfaction of fixing what once did not work sounds worth all the trouble, not to mention I'll be able to usefully apply when completed. I just tried with a 12V power source and nothing happened. However, I did get a static sound when the red wires were all connected. The black had to be touching, when the black wasn't touching and the red was I got nothing with wire contact for black wire. This static seems hopefull but I don't know what is causing the problem of the fan not spinning.

Reply to
rdeol85

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.