USB cables with different 'lumps' for different uses?

Discussion in 'Digital Photography' started by David, Oct 8, 2003.

  1. David

    David Guest

    I have now accumulated several USB peripherals - printer, digital
    camera, webcam, memory card reader and scanner; however almost all the
    cables originally provided with each device are slightly different in
    that they mostly have a large plastic 'lump' near one end of the
    cable. (Reminds me of a snake that has just swallowed a rabbit!)

    I have always used the original cable provided with teach peripheral,
    however, now after re-siting all my equipment I need to buy some
    slightly longer leads for them to reach.

    Do these cables actually differ? What are the 'bumps' for; are they
    crucial? Do I need to specify anything specific for different
    peripherals? Do cables for USB 1.1 and 2.0 differ?

    Thanks for any help
    David, Oct 8, 2003
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  2. David

    JackD Guest

    Those lumps are a ferrite core which is used to reduce "ringing" within the
    cable. Basically it keeps the electromagnetic waves produced by the
    electrical signal from reflecting and causing problems within the line. The
    manufacturer has placed them where they provide the most good and are most
    convenient. Different cables can have different properties due to shielding
    and other things, so it makes sense to use the right cable for the right
    device, but if another one works then it works so you can use it.

    I'm not sure if there is enough difference between USB 1.1 and 2.0 to
    require different cables unless the 1.1 cables were marginal to begin with.

    JackD, Oct 8, 2003
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  3. David

    Eric Gisin Guest

    If these are standard A-B cables, you can replace them with quality
    cables up to 15'.

    Your old cables should reach if you add a hub or two.
    Eric Gisin, Oct 8, 2003
  4. David

    EktarEd Guest

    The bumps you refer to are for noise suppression.
    EktarEd, Oct 8, 2003
  5. David

    Red Clay Guest

    Red Clay, Oct 8, 2003
  6. David

    Eric Gisin Guest

    Just look for a brand name. No name stuff is suspect.

    All A-B cables are shielded. I don't know if that RFI "blob" is
    required, my old printer cable doesn't have it.
    Eric Gisin, Oct 8, 2003
  7. David

    Joe Pfeiffer Guest

    The "bumps" are ferrite cores for noise suppression. You should be
    able to switch cables at will.

    Near as I can tell from looking at, 1.1 cables and 2.0 cables
    are identical (see
    I also note that the most common packaging I see on USB devices and
    cables (version number of the standard) is specifically discouraged by
    the USB Implementors Forum!

    Any cable with one of the logos shown at that web page should be
    compatible with all of your devices, whether they are USB (1.1) or
    Hi-Speed USB (2.0). I have no idea whether the forum has any kind of
    teeth to prevent a manufacturer from marketing a sub-standard cable,

    Bottom line: swap the cables all you want. It should work just fine,
    and it certainly won't cause any physical damage even if it doesn't.
    Joe Pfeiffer, Oct 8, 2003
  8. FWIW my printer didn't come with a cable so I bought one for 39p ($0.50).
    Works great. I use my Sony cable that came with my digital camera for
    everything that has the correct connector (an MP3 player and a removable
    disc drive). These also work identically with that cable.

    Andy Cunningham, Oct 8, 2003
  9. I certainly don't pretend to be an expert on cables, but recently I
    did some changes in my home office and my original USB cable was too
    short to reach my Canon Scanner. I bought a new one (high quality,
    high price) that was 15' long (Longer than I needed, but they didn't
    have any shorter ones) and from then on I had trouble. After
    installation, the computer was erratic in recognizing the scanner. I
    even went so far as to uninstall and reinstall the software. A friend
    tipped me that 15' just may be too long, as the USB carries power, as
    well as signal. I finally got hold of a shorter one (10') and my
    problems went away.
    E. Barry Bruyea, Oct 12, 2003
  10. David

    Trevor Noble Guest

    You can get a little plug/socket USBa/USBb adapter that allows you to daisy
    chain a number of UDB cables together in your local electronics/computer
    store. Gives you flexibility to swap peripherals with ease.
    Trevor Noble, Oct 12, 2003
  11. David

    Paul H. Guest

    Just thought I'd add that several companies make "amplified" USB cables
    which sell for $20-$30 US that let you go well beyond the the ten-foot
    limit. By sandwiching one of these cables between two ten-foot unamplified
    cables, I was able to use an inexpensive USB webcam as a security camera
    placed about 30' away from my computer.

    BTW, signal degradation is far more likely to have been the source of your
    scanner problems--cable capacitance can effectively short out data at high
    transmission rates.
    Paul H., Oct 12, 2003
  12. David

    Eric Gisin Guest

    Officialy, 5m=17' is the max. I don't think power is the problem with
    your scanner, the twisted pair may be.

    Here is a good USB FAQ:
    Eric Gisin, Oct 12, 2003
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