Use as UBS Extension?


#1

Can I use two USB 2.0 Gigabit adapters to create a reliable, USB 2.0 extension over CAT-5 (50 ft)?


#2

Hi Tom,

Nope, this isn’t the right kind of product for that!

This is a USB adapter that adds a an additional network interface to your computer. You’d want to do that if your existing network interface has failed, if this one is faster (e.g. if you were previously running 100Mbps ethernet on a Gigabit capable network), or if you want to do advanced routing or point to point network connection stuff with a second interface.

What you’re looking for is a USB over Ethernet solution – and those do exist, however we don’t sell any because we haven’t yet been happy yet with the solutions (they’re getting better, though. The least costly solutions involve virtual USB driver software to capture the USB device traffic and route over the ethernet network).

One suggestion: to get 50 feet distance with maximum compatibility, you’d be better off staying with USB cabling if possible. E.g. chain two of these adapters: http://www.amazon.com/Plugable-Meter-…

Note: the active extension cable is powered by the USB bus itself. So each one consumes a little bit of USB’s 500mA bus power, so you may need a powered hub at the end if you’re not connecting to a self-powered device or hub (that is, something with its own AC adapter into the wall).

Thanks for the question!
Bernie


#3

THANKS, Bernie. The application is this: A camera sits at the top of a 50’ mast and is controlled by a computer (running Breeze Systems DSLR Remote Pro) on the ground. USB 2.0 speed is _required_ to allow control of focus, etc. I am doing this today with a pair of ICron passive extenders over CAT-5 and it is not OK.

Since the camera has a battery, I think it is considered self-powered. So two of these cables would give me USB 2.0 ?!?!? That would be ideal (and a lot less expensive than I thought)

Tom


#4

Hi Tom - thanks so much for the additional detail on your scenario!

Yes, I think we can find an inexpensive pure USB 2.0 solution that will work for you (assuming you can have USB cables and small adapters attached to the mast).

A quick question, though, which might shift my product recommendation. Are you using the DSLR for video or still capture?

The USB specifies max cable length of 5 meters. The product linked above pushes it up to 10 meters with a good repeater and heavily shielded cable.

But if you’re doing any real-time motion video capture, that can be timing sensitive (at a low level, uses isoch transfers), so I’d stay within the limit of 5m per repeater. So instead of buying 2 of the 10 meter adapter above, I’d recommend 3 or 4 units of this shorter 5 meter repeater cable:
http://www.amazon.com/dp/B003SA5UKE/

USB 2.0 spec allows up to 5 devices/hubs/repeaters to be chained 5 deep, so you’ll be good there as long as the first repeater is connected directly to a host port. And for a DSLR with its own battery, power should be fine in either case.

If you can, let us know here how things went after the purchase! We’ll help where we can, and if you find anything doesn’t work, returns are easy.

Thanks!
Bernie


#5

The DLSR is a Canon XSi, which allows “Live View”. The view from the sensor is transmitted to the computer and is used for framing, focus, exposure, etc. But the speed of this “video” is not important. The speed of reaction to the focus input IS important to prevent typing ahead of the buffer and over-shooting. So while it is not “video capture”, video is involved. Timing is important, but it is at the GUI-Human level.

A chain of these small devices is not a problem. I would use some sort of “retainer” to ensure the usb connections do not come un-plugged.

I’ll give these a try and will report back.

Thanks,

Tom (Phoenix)


#6