Quick, easy and cheap gadget makes unused USB ports blink.
By: AlphA

Got unused USB ports? Make them blink! Why not?

Okay. So, this isnít my most impressive project. But, itís so simple and silly I believe others could have fun with the idea, just as I have.

I have found something to do with unused USB ports. I call it U-S-Blink and they are quick, easy and cheap to make. This is another product of boredom.

Parts needed.

All that is necessary to create a U-S-Blink is a PCB with long trace leads, a Flashing LED, a soldering iron and some solder. I used an old RadioShack PCB which was laid out like a protoboard/breadboard and a Flashing LED snagged from a blinking lollypop once I finished devouring all of the sugary deliciousness.

Since Flashing LEDís actually contain super small integrated electronic circuits for oscillation, a current limiting resistor isnít necessary in most cases. This makes this project embarrassingly easy. Staying within the voltage range is still important. I didnít have the specs for my LED, but +5VDC usually falls within the range of most blue SuperBright 5 mm Flashing LEDís.

Not absolutely necessary was the rectangular black thing in the above image. I noticed that some older USB ports did not hold the PCB in place. It was necessary to adhere a thin, smooth object to the back of the PCB to make it a bit thicker. My "thickener" ended up being a piece of zip tie.


After cutting the PCB and filing the edges to match the width of USB ports, I dremeled a small notch for the LED. This helped to secure the LED while making the unit even smaller.

USB +5VDC and ground comes from the edge conductors. Pin 1 is 5VDC while 4 is ground. Reversing the polarity a typical LED will not harm anything (it simply restricts current flow and doesn't illuminate). However, a flashing LED can be damaged if not oriented correctly. LEDs usually have a longer lead representing the anode (+) and a flat side with a larger interior on the cathode (-) side. More information on USB pinouts and flashing LEDs can be found online.

Some flashing LEDs have no flat sides, the interior sides are equal in size with leads trimmed to the same length. If you run in to one of these, and you do not have the specs, flashing LED's give you one last hint on determining proper orientation. I have found that if you look closely at a flashing LED, the IC circuit (very small black square) is on the side of the anode.

I tinned the traces for added conductivity.

The tinned traces in the image above appear thicker than they actually are.

The fruits of my labor depicted below:

U-S-Blink blinking away

Yes, I stood there and took several pictures until I
caught it in its ON state.

U-S-Blink also works with PS2 to USB adaptors- great if you donít have spare USB ports. Finally, a use for those PS2 ports!


They don't call them "SuperBright" for nothing.

If nothing else, I have discovered a thrifty way to make USB A jack connectors. If you are unsure of the usefulness of a U-S-Blink, find someone who turns their computer off when not in use, fill their unused USB ports with U-S-Blinks (especially if they have USB ports in their monitor) and watch their reaction as they turn their computer on to discover many brightly colored lights flashing asynchronously.





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