HP Printer USB / Power Cord Issue - Bizarre

Archived from groups: microsoft.public.windowsxp.print_fax,comp.periphs.printers (More info?)

Customer has an HP 1300 Laserjet and intends to use USB.

Many attempts to make it work failed - apparently affecting the setup of the
DOT port.

Finally noticed that HP recommends plugging the printer's AC power into the
wall and not into a power strip *and* to use the power cord supplied with
the printer. Doing the former (and maybe the latter, I don't know) solved
the problem!

Hypothesis:

The printer has a very susceptible power supply that can't stand any
filtering between the printer and the source of AC power.

Any others? Comments?

Thanks,

Fred
1 answer Last reply
More about printer power cord issue bizarre
  1. Archived from groups: microsoft.public.windowsxp.print_fax,comp.periphs.printers (More info?)

    "Fred Marshall" <fmarshallx@remove_the_x.acm.org> wrote in message
    news:eoz4s1RbFHA.724@TK2MSFTNGP12.phx.gbl...
    > The printer has a very susceptible power supply that can't stand any
    > filtering between the printer and the source of AC power.

    Well it might be that but I suspect it's not quite that exactly....

    It's possible that a loop exists and that noise on the mains or another
    source is coupling into this loop and preventing or corrupting the data on
    the USB cable. I've seen two pieces of equipment that work fine on their own
    but which fail/crash when they are connected together. A typical loop might
    be...

    power lead of computer
    case/0V of computer
    cable/cable screen
    case.0V of printer
    power lead of printer

    The loop may not be exactly like that - it can involve capacitive coupling
    between signals that aren't connected together directly. It can be very
    difficult to fix this type of problem as both manufacturers can claim their
    kit is ok. Sometimes they are forced into this position by the standard for
    the interface cable between them.

    Solution: What's usually important is the AREA of the loop so one possible
    solution is to try and reduce that - perhaps by moving equipment closer
    together, shortening data cables and removing extension leads or otherwise
    changing the physical layout to reduce the area. I've had to resort to
    twisting the mains leads together and plugging them into adjacent wall
    sockets or adjacent sockets on a filtered mains block.

    This can sometimes be a bitch to fix. Sometimes doing the opposite of what
    the theory tells you works for no obvious reason! You can hire monitoring
    equipment that monitors and records mains transients so if the problem comes
    and goes you can try and correlate the two.

    Some makes and models of equipment are probably more susceptible than others
    but I've no idea if this is true of the kit you mention.

    Is this in a factory? Got any manufacturing equipment nearby? Radio
    transmitters? Air conditioning units?

    Colin
Ask a new question

Read More

Printers Hewlett Packard USB Power Peripherals