Ok, this goes to all my computer-savy friends: A real life riddle (to which I haven’t gotten a convincing answer)

Everything started with a problem that I have with my Macbook: The USB ports are just too close. Way too close. It is practically impossible to connect 2 USB devices at the laptop (unless, of course, I’m using cables).

In fact, if you try to connect two USB Flash Drives directly to the Macbook, its quite possible they won’t fit at the same time, or if they do, they would be too tight and you may be running the risk of damaging the flash drive, the usb port, or both.

Here are a couple pics that show my frustration trying to connect two USB flash drives at the same time.

Well, the thing is, my USB wireless broadband card its the 3G/4G from Sprint. It’s quite big, and it is impossible to connect anything else when that monster is connected (which, I have to say, is 99% of the time).

So, I went with my Radio Shack pals to look for a small USB extender or something like that. They didn’t have it, but I did find a sale on a USB hub from Gigaware ($9 dollars, not bad). Although it has 4 ports, one of them is too close together to other two ports. Anyway, that gives me the ability to connect 3 USB devices.

Problem solved, right?

Wrong! I connected my Sprint air card... and it didn’t work. The Macbook won’t recognize the device.

When the card is connected by itself, I can see 6 green bars in my Macbook. That means I have a good signal.

When the card is connected through the USB hub, there is no bars (although the card itself lights up).

I asked my good friend Google what could it be. After some research, I got a disappointing answer.

Apparently is a known issue: Sometimes the wireless internet USB devices won’t work if you connect them through a USB hub. Why? Well, a USB device (without external AC power) draws its power from the computer. If you connect a USB hub, you are pretty much splitting the electricity between the hubs. So, when your USB device needs lots of energy and relies on getting 100% of the available electricity from the USB hub, well... it simply won’t work. 

And most of the USB cards need all the electricity available through the USB hub. Actually, there are USB hubs that are not “Self powered”, but powered from an external AC adapter.

I also found that USB ports in a same computer might have different power output. At least, that’s the way it is on my Macbook Pro. I tried all possible combinations, just in case, but no success.

Disappointed, I was about to return the USB hub to the store. Although, for 9 bucks, I thought on keeping it.

Anyway, while wondering what to do, I remembered that I had to charge my iPod. I didn’t really needed to be online at that time, so I simply plugged in the iPod to the USB hub. I didn’t think too much about it.

As expected, the iPod connected, started syncing, and started the charging process.

And that was when a green flickering from my screen caught my eye.

The Aircard started, with all 6 bars! I clicked on “Connect” and it connected just fine!

I tried this several times. And these are the facts:

1. -The card by itself on the USB hub doesn’t work.
   

2. -But if I connect the iPod and the Aircard at the same time, they both work!
   

I don’t understand why... my (apparently flawed) logic tells me that, if at all, they should work when only one is connected and stop working when both are connected.

I’m happy, as my USB works for my intended purposes, as long as my iPod is also connected.

Although I don’t understand why.

My question to you: Why does it work this way?