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slofox
27-07-2005, 04:00 PM
Are USB 1.0 and USB 2.0 cables interchangeable? Have just bought a coupla USB 1's but have chucked the USB 1.0 machine off the bridge and am getting one with USB 2......do I have to replace the cables?

Rob99
27-07-2005, 04:02 PM
Good question, all I know is that they will work, weather they will go full speed USB2 is a different story.

Speedy Gonzales
27-07-2005, 04:08 PM
Yup the cables should work or fit, but the speed might not be USB 2 speed.

martynz
20-08-2005, 05:09 PM
I had the jawdropping experience in a major UK High Street electronics store (Dixons) of being told that all you needed to upgrade from USB1.1 to 2.0 was cables with goldplated connectors.
Am I being anal in worrying about not having labelled all my USB cables? Some manuals say you should use the provided cable. But most aren't labelled and unless you do it straight away...oops.
But I have some with little cylindrical barrels, are these ferrite RFI suppressors and are they necessary?

Martynz

Speedy Gonzales
20-08-2005, 05:19 PM
Nup i doubt that. If u have USB 1.1 getting a cable thats gold plated wont make it USB 2.

If that were the case, newer mobos wouldn't have USB 2 onboard.

We'll still be in the ice age! Being in the ice age with broadband is bad enough!


Well, I would say if u have something USB 2, its better to use the cable that came with it. Depending on what you're using (whether its a 1.1 or 2 cable), you may not notice the diff.

Poppa John
20-08-2005, 05:29 PM
What IS the physical difference between USB 1 & 2, anyway. PJ

Speedy Gonzales
20-08-2005, 05:37 PM
http://www.everythingusb.com/forums/showthread.php?threadid=809

If u mean in speed a LOT of difference.

martynz
20-08-2005, 08:13 PM
Thanks for that link Speedy. The various posts included:
"While many cables have "High Speed" or "Ver. 2.0" written on the insulation, there are many cables without such writing that do meet the standard and work fine."
"Since a 2.0 cable is shielded, there ought to be electrical continuity between the metal shrouded ends. If not it isn't shielded."
"Authorized USB 2 cables have a "High Speed USB 2" label attached to one end, usually wrapped round the cable and the label ends stuck to each other. This is usually quite prominent and cannot be missed."
I'll now read the small print very carefully and check the electrical continuity. But I've never come across the 3rd one re. labelling.
No one has answered my query about the (?) RFI screening barrels.

Martynz

Speedy Gonzales
20-08-2005, 08:20 PM
No one has answered my query about the (?) RFI screening barrels.

Martynz

Never heard of these. And dunno what you're talking about.

pine-o-cleen
21-08-2005, 02:12 PM
...
No one has answered my query about the (?) RFI screening barrels.

Martynz

Why would manufacturers go to the trouble of putting them on if they weren't neccessary? My logic anyway.

Graham L
21-08-2005, 02:34 PM
Good quality USB1.1 cables should work perfectly on USB 2, if they are not too long. I would be dubious about the maximum length ones (5m) working. 2m and less will probably work.

If they don't "work", they do that by not running at the USB 2 speed.

It's the tranceivers at each end which decide what speed will work for a connection. If they can't work at the top speed, they cut back to 1.1 speed.

The main difference between the cables is more tightly controlled impedance and losses in the twisted pair which handles the data. Remember this is UHF signalling in a transmission line. The power wires are not as critical, but I have seen some cables with heavier power wires. (Not much heavier, just a couple of gauges in the area of 24 to 26 SWG).

I don't think the standard requires a shield ... the twisted pair is intended to give the noise immunity. It's a balanced cable.

Like all "commodity" cables, there are various qualities on the market. Some are much cheaper than others. Some are better than others.

It costs nothing to try a cable you've got. If it works, put a tag on it for future reference. But it might not work on a different USB 2 device. ;)

Shortcircuit
21-08-2005, 03:44 PM
I have just purchased a usb2 storage device, comes with a short cable with 'RFI bulge' near one end. I also have a usb 1.1 cable for a camera (with the same bulge). both cables are virtually identical with no apparent indication if 1.1 or 2.0 on them.

The only thing I can find on the new usb2 cable is a very tiny number '2' on one of the plugs on the round part just where it changes into the flat rectangular head of the plug. Can't say if all usb2 plugs have this, or if it is meant to denote usb2 connectivity, but maybe you can look on your cables (it's pretty hard to see though!)

This could become an issue with a few different 1.1 and 2.0 cables lying around unless you own a crystal ball :D