HELP: External 250G USB screwed with GParted

Tim ignored_mailbox at yahoo.com.au
Mon Jan 21 04:53:20 UTC 2008


Tim:
>> But I'd tend to challenge their assertion.

   [that any old cable will do]
   
>> There's a huge increase in speed between the two, and that means a
>> very large bandwidth change.  It's a much higher signal frequency in
>> use, and any crappy cable termination, or other cable
>> characteristics, will have a worse effect on it.

Craig White:
> When I don't have knowledge of something, I actually cite the best
> source I have and relate that I haven't seen any information that
> disputes it.
> 
> Here you have stated an argument without any evidence to substantiate
> your beliefs.

Did you do any research?  Do you know anything about the differences
between USB 1 and 2, the speed differences, at least:

Slow USB 1:  12 Mb/s tops
Fastest USB 2:  480 MB/s tops

Now, lets make a very simple conversion and say that the slower one can
put a 12 MHz signal through the cable, and the fastest 480 MHz.  Anybody
who works with RF knows that cabling and connections at high frequencies
are a crucial part of getting an undamaged signal.  They know that some
connectors are unsuitable for such a wide variance, and that's a very
wide one in this case.

If you pull apart some USB cables, you'll find some are decently
screened, with a proper brade, like coax designed for transmission uses.
And others are just four piddly wires with a crummy spiral wrapped wire
shield.  Never mind the quality of the terminations, or the lack of
decent strain relief against tugs on the cable.

There's certainly PLENTY of reasons to believe that some cabling is just
not up to the task of the 480 Mb/s rate that USB 2.0 can manage.

> Thanks for your theories...I would probably believe them if I hadn't
> caught you talking about things your didn't know in the past.

Nice try at playing the straw man game.

Which "Edge Technologies" were you talking about?  If it's just some
computer vendor, then I'd be not the slightest bit surprised that they
have no technical electronics knowledge, let alone RF theory.

It's clear you have no idea what you're talking about if you think that
a 480 MHz signal is going work fine through any bit of crappy wiring. 

-- 
(This computer runs FC7, my others run FC4, FC5 & FC6, in case that's
 important to the thread.)

Don't send private replies to my address, the mailbox is ignored.
I read messages from the public lists.




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