[Elecraft] Elecraft K3 DSP software wont load properly

[Guy Olinger K2AV]

This starts with the devices using the voltage on the USB port to
operate.  The support of that pin as a "hard" 5v voltage source varies
all over the map.  And it is altogether TOO tempting for a gizmo maker
to count on more current than is really available, making USB devices
running on 3.5 or 4 volts all too common.

The worst of these power dupes are passive USB hubs.  The worst USB
ports are laptops and cheep-cheep port cards which were never
engineered by anybody, where the 5 volts is via tiny circuit board
traces that quickly start to become resistive with any load at all on
the USB port. Some of these port cards have *passive* USB Hubs on
them, even though there is 5v available on the card pins to
reconstitute the supply voltage.  Just another reason that the
*U*niversal in USB is a joke.

73, Guy.

On Mon, Dec 6, 2010 at 6:55 AM, Jim Miller <jim at jtmiller.com> wrote:
> I discovered my new Dell Win7 laptop wouldn't load the K3 unless it had the
> external power supply hooked up. It wouldn't work on battery alone.
>
> I use the lateest FTDI based KUSB.
>
> 73
>
> Jim ab3cv
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