USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

[PCBONEZ]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

You are knit picking at nothing.
If you take things in context in the first place you wouldn't get so lost.

.

[jpdoe]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

Sorry for my lack of clarity.
I don't really remember the actual instructions I read some years ago.
In a few days, when I'm not half sleep as I am now, I'll make an independent thread with a more detailed post.

Thanks for your answers.

[Fizzycapola]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

@ jpdoe: like arneson wrote, screening means shielding. Cheap cases use unshielded cables or "selfpromoted tecnicians" [euphemism for those barely capable of putting a motherboard into a case] don't connect the shield to the ground pin.

@ fizzy: I read only now you've troubles with a laptop: forget the unshielded cable thing.
Did you try connecting the devices to a powered hub?

Zandrax

That sounds like a good idea for testing purposes Zandrax. Though I'd rather not have to buy one of those if it can be helped. ( I think I'd rather buy some low latency ram instead for the same money hehe)

I wonder would it not be possible to make a passive filter instead using the smoothing power of Oscons. Something simple like penetrating the rear cable of the port inside the laptop and sneaking a few Oscons in, then seal up with liquid electronic sealant and shrink rap it to seal all oxidisation opportunity.

In the case of devices acting as antennae, by their leads, perhaps I will be more generous with my ferrirtes here. Alternatively, cannabalising unused screened cable. I could rehouse most of my device usb leads in a double layer screening and solder it at the socket entering end to the metal shroud. ( or not?)

Let me know if any of those ideas sound feasible.

[i4004]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

>If you take things in context in the first place you wouldn't get so lost.

you can be so fuckin' dense at times.
it's just not possible for you to be wrong, is it?

first of all you've read it in a wrong way, and then you've said only floating ground can cause g.loop, and now i'm lost?

i'm not nitpicking, it's what he said. it IS the context.

also, the complete answer is weird:
"What you are talking about is called 'floating grounds' [ground is not at earth ground].
That should not happen in a PC unless there is already a fault."

what should not happen?
floating ground will happen anytime electric installation of the place is not grounded.

so again, floating ground and ground loop are not the same thing.
and mistaking one for another doesn't make things any clearer.

and i want them clear because it's interesting subject and as i had a particular weird case recently, one that i'll probably document here.
perhaps in the jpdoe's new thread.

so i allow only good data on ground loops on this forum.
<wink>

[PCBONEZ]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

Of course I can be wrong. - But not this time...

A floating ground describes a circuit where the the ground's voltage is above earth ground.
[Greater than zero volts to earth.]

If you connect the ground on a circuit with a floating to the ground to a circuit with an earth ground (or to a floating ground at a different potential) then you create a current path. - That current path is called a ground loop.

And like I said.
If you could keep things in context you wouldn't get so lost.

.

[zandrax]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

That sounds like a good idea for testing purposes Zandrax. Though I'd rather not have to buy one of those if it can be helped. ( I think I'd rather buy some low latency ram instead for the same money hehe)

Matter of priorities: which do you feel more urgent between a working USB connection or slightly faster ram?

I wonder would it not be possible to make a passive filter instead using the smoothing power of Oscons. Something simple like penetrating the rear cable of the port inside the laptop and sneaking a few Oscons in, then seal up with liquid electronic sealant and shrink rap it to seal all oxidisation opportunity.

In the case of devices acting as antennae, by their leads, perhaps I will be more generous with my ferrirtes here. Alternatively, cannabalising unused screened cable. I could rehouse most of my device usb leads in a double layer screening and solder it at the socket entering end to the metal shroud. ( or not?)

Let me know if any of those ideas sound feasible.

[/QUOTE]I wouldn't open the notebook if still under warranty and I couldn't help you in any way in smoothing the signal. IMHO putting ferrites on already shielded cables is a better experiment to carry: try savaging them from old VGA cables.

Zandrax

[arneson]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

I have to deal with multiple grounds when installing shipboard systems.
The DC neg grounds can be 12v 24v and 32v all on one panel.
Then next to this will be a panel with 120vac neutral and 120vac ground, not to be confused with rf ground or sea water ground or bonding system.
There are times when cables must be connected to ground only at one end and other times when extra grounds from chassis to device have to be added.
I've put in radar antenna cables that have three large ferrites and an 8awg strap from the array case to the arch.
I read one manual that calls for the grounded cable shield to be connected in Canada and not connected in the US.
Grounding and ground loops can be tricky stuff, even more in a lightning environment.

[i4004]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random in

If you connect the ground on a circuit with a floating to the ground to a circuit with an earth ground (or to a floating ground at a different potential), or if you connect circuit with ground at one potential to a circuit with ground on another potential then you create a current path. - That current path is called a ground loop.

there , i corrected it for ya.

if you're suggesting ground with potential that differs from some other ground(ground at 0v...but what ground is perfectly 0? gold that goes straight to center of the earth?) can be called "floating ground", that's where you're wrong.
floating ground HAS NO CONNECTION to ground.
grounded points do, no matter what's the resistance between circuit vs. "good ground" and circuit vs. "bad ground".

got it? when something is grounded (even badly grounded) it's not floating anymore.
floating ground essentially means "no ground".

you're wrong in thinking only floating ground can produce g.loop condition.
two grounds at different potentials can do too.

[kikkoman]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

where's your fucking problem, guys?

[PCBONEZ]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

Thanks for the mis-correction i4004.

You made it redundant by saying the same thing twice.

kikkoman
i4004 and I are playing.
If you don't wanna play too then don't jump in.

.

[i4004]

Re: USB woes: crashing, noise, bsod, wiping devices, destabilising, causing random input.

yes, if we don't mind, i don't think anybody should...hehe...

anyway
"A system where the system ground is not actually connected to another circuit or to earth (though there may still be AC coupling) is often referred to as a floating ground."

http://en.wikipedia.org/wiki/Ground_...d_versus_earth

bonez, it's not good if you have definitions only you know about...
hehe...