4PORT USB 2.0 Slim Hub Review

Pros: Compact, lightweight, built-in cable, option to power the hub
Cons: Feels a little cheap, does not come with power supply.

A note about USB 2.0: The maximum current that can be supplied over any port is 500 mA. The minimum is 100 mA, and it is allocated in 100 mA increments. This means that the hub can draw a maximum of 500 mA from the computer it is plugged into. Keep in mind that the hub is a USB device, and must allocate 100 mA for itself.

If only one device is plugged into the hub, then no big deal. That device can draw 100 mA, 200 mA, 300 mA, or 400 mA, which is plenty for most devices.

If two devices are plugged into the hub, the current can be split 100/300 mA, 200/200 mA, 100/200 mA, or 100/100 mA. Most devices are happy here. You only run into problems if one device needs more than 300 mA, or if both devices need more than 200 mA.

If three devices are plugged into the hub, the options are 100/100/200 mA or 100/100/100 mA. Problems can arise if any device wants more than 200 mA, or if two devices want more than 100 mA.

If four devices are connected to the hub, the hub can only allocate 100 mA to each device, leaving 100 mA to power the hub itself. This is fine for devices that are self powered and only use USB for communication (like printers, or syncing a PDA that has a powered cradle). USB flash drives are probably OK too. Charging an iPod or powering a radio (like WiFi or mobile broadband) takes too much current, and won't work.

Why 4 ports then? That is the maximum they can put and still be compliant with the standards. Plus, nobody wants a 2 port hub. Once you have the USB interface, it's really cheap to add more ports. This hub *does* have a jack for a power adapter, but doesn't include the adapter to save cost.

If you need a power adapter, Zonet packages this hub with a power adapter and calls it the Zonet 4 Port Usb 2.0 Hub W Power Adapter. Alternatively, look for a power adapter that outputs 5V (DC) and can supply at least 2.6A. You can get these online, or might have one laying around the house. With a power adapter, this should be able to provide the full 500 mA to every port, and everything should work fine.

Buy it here now!