How to Match USB Ports & Controllers?

[puntoMX]

Wow, I have a Developer and two Super Moderators helping with this! Who could ask for better than that?

But I have a real sense that I'm getting in over my head here. I do have a steady hand, as I said to dencorso, but otherwise when it comes to manual work, I'm all thumbs.

We are just people that love our job .

Now, you know how to use a multimeter, and the Power Supply Unit has way larger pins to test on. To make a contact between the green and black wire (power"OK"/power"ON") you can use just a simple paperclip. it's really easy even for some one that never did it before.

[dencorso]

Great!

And before doing anything, always do 3 sanity checks to get confortable with the multimeter (the manual leaflet is here for all to see):

1) Do the Continuity Check.

2) Set it to ohmmeter 10 and touch the test leads together: if you don't read zero, correct it with the resistance zero adjust.

3) Set it to DCV 10 and measure a brand-new common lantern battery. You should read 1.5V or slightly less.

Now, with this out of the way, set it to DCV 25 and proceed the tests puntoMX suggested.

[JorgeA]

Now, you know how to use a multimeter, and the Power Supply Unit has way larger pins to test on. To make a contact between the green and black wire (power"OK"/power"ON") you can use just a simple paperclip. it's really easy even for some one that never did it before.

puntoMX,

Umm, ahh, well -- nope, I don't know how to use a multimeter! I just purchased it on Monday for this project, but it's fast becoming clear to me that I am getting in WAY over my head here.

When I was in the 8th grade, we took a series of "aptitude" tests to measure our abilities in a wide range of areas: language, math, logic, mechanical, and so on. While I scored very well in all the "academic" subjects, I finished in the 3rd percentile for mechanical ability. The test consisted of about 400 sets of drawings of cardboard boxes with flaps of various shapes, including one that was put together and four that were disassembled. The task was to look at the disassembled boxes and select the one that, when put together, would look like the whole box nearby.

The drawings got more and more complicated as we got further into the test. After doing the first 25 boxes or so, I could no longer make heads or tails out of the drawings. They just didn't make any sense to me. I guessed on about the next 50, and then I decided to use the remaining time on that test to go back to previous tests and finish them (which was permitted). I ended up scoring lower in mechanical ability than 97 percent of all the students who took that test nationwide that year.

Prudence is the better part of valor, so I think that the wise thing for me to do at this point is to thank you and dencorso, and step back from this particular project for the time being, while I study the subject. This project concerns my main PC, and given the jungle of wires and cables that I saw in there the other day, I'm not sure that I could put everything back together at the end, even with a schematic. (Remember, drawings don't tell me anything!) At least till I get a better grasp of the concepts involved and the terminology.

I'm not rejecting the project -- I just need to think before plunging in!

Thanks very much (gracias mil) for the kind offer to help. Hopefully I'll be in a better position to accept it soon.

--JorgeA

[JorgeA]

Great!

And before doing anything, always do 3 sanity checks to get confortable with the multimeter (the manual leaflet is here for all to see):

1) Do the Continuity Check.

2) Set it to ohmmeter 10 and touch the test leads together: if you don't read zero, correct it with the resistance zero adjust.

3) Set it to DCV 10 and measure a brand-new common lantern battery. You should read 1.5V or slightly less.

Now, with this out of the way, set it to DCV 25 and proceed the tests puntoMX suggested.

dencorso,

Your reply and that of puntoMX convinced me that I constitute an immense risk to the health of my most important computer. There's a lot of new terminology in those posts whose meaning I don't know.

This tells me that I have no preparation or understanding to do this project, nor is my mind geared to easily grasp the underlying (mechanical/electrical) concepts. (See my reply to puntoMX.) It's going to take some studying of the concepts and the vocabulary before it's safe for me to actually work on the PC's insides, as opposed to just peeking in.

Not that I'm against stretching my mind. Not at all. In recent months I've done things with computers that a year ago I'd never have imagined possible for me -- putting in a new hard disk, partitioning it, installing a new operating system, setting up a home network. With your help and that of the other great folks here, I've been able to do these things.

And I'm still working in that direction (see my post in the Win98 section). But getting into testing electrical connections is a whole different animal, and one that I need to get to understand first before playing with it.

So let me research this for a bit so that I can come back when it all doesn't look so unfamiliar and dangerous.

Thanks very, very much for your help on this, as on so many other issues. I look forward to picking it back up.

--JorgeA

[dencorso]

OK! Take your time, JorgeA. It should be a pleasure, not an ordeal.

[puntoMX]

When I was in the 8th grade, we took a series of "aptitude" tests to measure our abilities in a wide range of areas: language, math, logic, mechanical, and so on. While I scored very well in all the "academic" subjects, I finished in the 3rd percentile for mechanical ability.

Don't let you drag down because of this; you are just lacking a bit of imagination and creativity. It's also not easy what you have learned to apply well in life. If you are open for it you will even build your next PC! For real, a lot of people never touched the inner hardware before and just started doing it with or without the help of us. You will see .

Don't forget to thank jaclaz, remember, he is the guy that always posts a lot of links in his replies and we love him for that.

[JorgeA]

Don't let you drag down because of this; you are just lacking a bit of imagination and creativity. It's also not easy what you have learned to apply well in life. If you are open for it you will even build your next PC! For real, a lot of people never touched the inner hardware before and just started doing it with or without the help of us. You will see .

puntoMX,

Part of what's going on is that I've been learning a lot of new computing stuff in other directions. I'm setting up a home network including PCs from three different Windows versions, which presents some challenges. So another reason to pause here is so that I can focus on that project.

I think I do have my share of imagination and creativity , but obviously I haven't yet applied it to electronics. I do intend to come back to this, but first I want to get this other project out of the way -- and especially to learn how to work inside the computer safely.

Don't forget to thank jaclaz, remember, he is the guy that always posts a lot of links in his replies and we love him for that.

jaclaz has indeed given a lot of help here and in other threads, so if you are reading this:

@jaclaz: Thank you.

--JorgeA

[jaclaz]

Now, you know how to use a multimeter, and the Power Supply Unit has way larger pins to test on. To make a contact between the green and black wire (power"OK"/power"ON") you can use just a simple paperclip. it's really easy even for some one that never did it before.

Please take note that some older/cheaper PSU did/do not handle correctly being powered on without an even minimal amount of power being drawn from the 5V or 12V lines (or both).

The paper clip is of course valid for ATX PSU ONLYand NOT for AT, since you mentioned having some "vintage" machines, be aware of the problems that you may find.

With all due respect for the advice given before, DO NOT power on a PSU NOT connected to something, of be ready and VERY quick in switching it off if needed (typically they would make a whistling sound) if you keep them powered on and they "whistle" they will simply BLOW in a matter of several seconds.

Mind you I am not trying to put you down or scare you, and I am not saying that your PSU will be one of those, but it may be.

The "old school" trick was to use a car tail lamp, 5W+21W:

Measuring the voltage of a "disconnected" switching power supply may anyway give "false" results, I've seen too many seemingly good PSU's that simply failed to work when some power was drawn from them to trust anyone, in any sense, a test of a PSU not connected to "anything" may be a waste of time.

For the record, you might want to notice how both of us advised you to buy a digital multimeter and you ended up buying an analog one.

Actually analog ones ARE better IMHO, though they are somewhat more difficult to be operated "properly".

Since you all were missing a nice link , here it is :

http://en.wikipedia.org/wiki/Parallax

Finding the reason why there is a mirroring surface on the scale is left as an exercise to the reader.

jaclaz

[puntoMX]

Please take note that some older/cheaper PSU did/do not handle correctly being powered on without an even minimal amount of power being drawn from the 5V or 12V lines (or both).

Now I must say that I never got a PSU in my hands that didn't power up unless it was bad, read, already going out or a very bad design.

The paper clip is of course valid for ATX PSU ONLYand NOT for AT, since you mentioned having some "vintage" machines, be aware of the problems that you may find.

Well, there are exceptions for sure, but when we talk about onboard USB 2.0 I don't believe I have seen anything not using ATX power .

With all due respect for the advice given before, DO NOT power on a PSU NOT connected to something, of be ready and VERY quick in switching it off if needed (typically they would make a whistling sound) if you keep them powered on and they "whistle" they will simply BLOW in a matter of several seconds.

The whistling sound you are talking about you hear when there is a short circuit or a bad circuit, again, I still have to find a PSU that blows up by itself if there is no load.

Measuring the voltage of a "disconnected" switching power supply may anyway give "false" results, I've seen too many seemingly good PSU's that simply failed to work when some power was drawn from them to trust anyone, in any sense, a test of a PSU not connected to "anything" may be a waste of time.

Correct, but we are talking about the 5VSB line and that should be around 5V, always, even when there is no load on the USB.

Just my 0.02, but I could have been wrong with the last 2000 different brand and model PSUs I tested . Ow, by the way, PSU testers are cheap these days.

BTW, El-Cheaper:

http://www.multimeterwarehouse.com/DT830BMinif.htm

Cool stuff, and cheap!.

[JorgeA]

Uh-oh -- When even the experts disagree as to what should be done and what the risks involved are, am I glad that I stopped myself before jumping into the abyss!

Nonetheless, I have every confidence that you guys will sort this out to a clearcut solution.

--JorgeA

[jaclaz]

@puntoMX

JFYI:

http://www.wikihow.com/Convert-a-Computer-ATX-Power-Supply-to-a-Lab-Power-Supply

http://web2.murraystate.edu/andy.batts/ps/powersupply.htm

Guess why a pre-load resistor is used?

Basically modern PSU's have an auto-switching pre-load, older ones DO NOT have it.

See here:

http://www.rcuniverse.com/forum/m_5680951/tm.htm

(actually PSU testers do usually have a resistor for load inside)

jaclaz