Sunday 8 June 2014

Wires, wires everywhere...

One thing you may have noticed around here is that we like our gadgets and tech, and not just in the kitchen. Smartphone? Tick. Tablet? Tick. E-readers? Tick. Consequently we each have a charging station at our bedside that looks like this:


Wires, wires, everywhere. Plugs that are chunky and take up space, coupled with bedside lights and other odds and ends (cup of tea - very important), and it's getting unwieldy. It's a daily battle to keep each wire running in a different direction to stop things ending up in a tangled mess. We've long been debating ways of tackling this, and with the move in the last few years towards all gadgets charging from a USB socket we finally made a decision. USB sockets mounted in our bedside tables.

One thing you might not know is that I'm an Electronic Engineer. While my day job is in the world of software I don't like to pass up an opportunity to get my soldering iron out at the weekend. Add this to Joe's love of D.I.Y. electronics and this task was well within our remit. 


WARNING: Things from here on might get a little technical, though I'll try not to go too far. Feel free just to look at the pictures!

First things first. What does a USB socket look like and how does it work, you ask? There's a picture below for you and it consists of two slots for USB cables and a set of four pins. Two of the pins are for power and ground, the other two are for data signals. In general you only need to connect up the power and ground in order to charge your device, the data signals are used for transferring data to and from your computer. Some devices (<cough>apple<cough>) also need fixed voltages on the data inputs in order to charge. 


Unfortunately some of our gadgets fit that description so we needed to cater for them as well.

Joe set about cutting neat holes in the top of our cabinets to neatly fit each socket. This didn't take him too long with a trusty chisel. 



Next we set about prototyping the circuit we were planning on making to check that it would actually charge things. It was a good job we did this as it was only at this stage we discovered we needed the extra voltages on the data in pins. 


Here is the circuit diagram (should you wish to replicate this yourself): 


Then we soldered all of that in place. To keep things as small as possible we soldered the legs of the resistors to each other and then directly to the pins on the socket before isolating it all with electrical tape.

Finally we attached them to the tables using Polymorph and screws which have created a really solid mounting point. If you've not come across Polymorph before we'd recommend it - we use for all sorts of odds and ends. 


And that's it. So far we've completed step one - to get a USB socket mounted and powered from our normal charging plugs hidden away in a draw. Hopefully at some point we'll get these connected up to transformers, allowing us to plug in the bedside table as a whole and power not just the two sockets, but also a lamp each. But that's for later...

The finished article

Happily connected to, and changing, Joe's phone.