USB Self-powered/Bus-powered Hub

Keyspan (a division of InnoSys, Inc.)
(510) 222-0131
List Price: $39
Available at the Applelinks Store

Review by Gary Coyne

USB is a wonderful peripheral connection mechanism for computers. It offers hot-swapping so you can unplug your mouse and plug-in a joystick, or unplug the printer and plug-in the camera. But this capability begs two questions: Have you ever noticed that USB ports are always placed on the back, or the "hard-to-reach" side of computers? And, considering the number of USB devices that are flourishing, have you ever wondered why the default number of USB ports provided on a computer is two?

Well, this article isn't going to try to answer these questions. Rather, it will offer a solution: Keyspan's Self-powered/Bus-powered hub.

This seemingly simple device doesn't do much, it just sits there ready to receive up to four USB devices. By plugging it into one of the USB ports in the back of the computer, the hub itself can sit right by your monitor or some other convenient location on your desktop ready for you to hot-swap and add all the USB components you care to add as well as more hubs to obtain the USB limit of 127 devices.

My computer has a USB PCI card and using either Apple's OS USB Driver 1.3.5 (for System OS 8.5.1 or 8.6) or Driver 1.4.1 (for System OS 9), the Keyspan 4-port hub worked just fine, true plug-and-play. On my kids' iMac, the Keyspan worked just as well.

Depending on what you attach to your hub, you can either use the hub as is (Bus-powered) for (DC +5V) 100mA power, or plug in the provided transformer to provide (Self-powered) (DC +5V) 500mA of power. There are several LEDs that let the Keyspan 4-port tell you what's happening, if one red LED light is on (the one on the right), that means you are in Bus-powered mode (the port is taking its power from the computer's USB port). If the other red LED is on (the one on the left), this means the transformer is successfully providing power to the port and you are in the Self-powered mode.

There are also 4 green LEDs on (one over each USB port) showing that power is reaching each of the ports.

I did find one quirk with the unit: if you unplug the power from the transformer at the 4-port unit itself, the 4 green LED lights go off. If you unplug the transformer from the wall (simulating either no power coming from that wall socket or a break in the wire from the transformer to the 4-port unit, the 4 green LED lights stayed on. I don't believe this behavior is correct.

Aside from the obvious application of providing more USB ports, I found that by placing the hub in front of my monitor provided easy access to the port for easily plugging devices in and out. Although items like printers may not need this capability, I found that this simplified my use of other devices like cameras. Even if you don't need extra ports, I found the easy access to a port reason enough to get one of these hubs.
Available at the Applelinks Store

May 26, 2012