USB Switch (not hub; not KVM)

[Andrew Merton]

I need to constantly transfer files between two networks (corporate &
analysis) that *cannot* be connected directly. Currently, we copy files
to a USB flash drive on a machine on one network, then move the flash
drive onto a machine on the other. Very tedious, especially as we do
this at least once/hour or thereabouts...

Is there any reason I shouldn't build a 4PDT switch in a box - plug the
flash drive into the box connected to the centre of the switch, wire USB
plugs to the two outsides (poles), and stick one plug into the laptop
and one into the corporate m/c?

Only one side is ever connected at a time, so there shouldn't be any
problems with connecting two +V together, and since the cables would be
short (<2m, .5 meter each side) the lack of termination shouldn't be a
problem, should it?

I can build this for around NZ$20 (US$30-40, I think) (I can't believe
a 4PDT switch is so expensive!), so it seems to be cheaper than buying a
commercial one. Note that we can't use a hub since that would
effectively connect the two networks together, which is a big no-no...

 

[andrew queisser]

I need to constantly transfer files between two networks (corporate &
analysis) that *cannot* be connected directly. Currently, we copy files to
a USB flash drive on a machine on one network, then move the flash drive
onto a machine on the other. Very tedious, especially as we do this at
least once/hour or thereabouts...

Is there any reason I shouldn't build a 4PDT switch in a box - plug the
flash drive into the box connected to the centre of the switch, wire USB
plugs to the two outsides (poles), and stick one plug into the laptop and
one into the corporate m/c?

Only one side is ever connected at a time, so there shouldn't be any
problems with connecting two +V together, and since the cables would be
short (<2m, .5 meter each side) the lack of termination shouldn't be a
problem, should it?

I can build this for around NZ$20 (US$30-40, I think) (I can't believe a
4PDT switch is so expensive!), so it seems to be cheaper than buying a
commercial one. Note that we can't use a hub since that would effectively
connect the two networks together, which is a big no-no...

You can buy commerical versions of this (google "USB switch") so I think it
should be no problem. Most of the commercial ones feature "auto switching"
which could be a security risk in your situation.

You may be able to find an old manual VGA or parallel port switcher and
reuse that.

Andrew

 

[Tom Biasi]

You can buy commerical versions of this (google "USB switch") so I think
it should be no problem. Most of the commercial ones feature "auto
switching" which could be a security risk in your situation.

You may be able to find an old manual VGA or parallel port switcher and
reuse that.

Andrew

If you build your own you will get many headaches at that data transfer
rate.
Off the shelf switches have a wide range of characteristics at high baud.
Tom

 

[crazy frog]

ive had the same prob needing a 30second to 60
for a automation project, so built my own.
ajustable from 0-60sec to delay switch on
wile the pc boots so my relays dont flicker.
no 555 timer in this circuit.
just a large cap to do the timeing.
i could send a circuit to youre
email if you want it.

 

[crazy frog]

wrong post site

 

[Rich Grise]

You can buy commerical versions of this (google "USB switch") so I think it
should be no problem. Most of the commercial ones feature "auto switching"
which could be a security risk in your situation.

Ask for an "A/B" switch:
http://www.google.com/search?q=USB+"A/B"+switch

Cheers!
Rich