is Useful

For a while now I’ve noticed an annoying hum coming from my home sound system, simply a Pioneer A400 connected to a Sony Blu-ray and our Samsung LCD TV. As today is lovely and sunny it seemed like the perfect opportunity to try and sort it all out. Hums in home hi-fi systems generally indicate bad earthing somewhere, the question is where. Time to get my geek debugging hat on.

First up - establishing that the hum is not coming from the amplifier. To do this I disconnected all external devices. Voila, the hum disappeared. That was a good start. Then I started to re-connect various devices to see when the hum returned, in this case it was when either the TV or Blu-ray were connected. Hmm. Why both? Perhaps my older amp doesn’t like these devices I thought.

Next up, I checked if the hum was being picked up from a power supply by the connecting wires. So all the wires came off and were routed round the front of the console. Nope, the hum was still there. Another possible cause removed.

Eventually I tracked down the source to the TV, as it turned out the blu-ray hum stopped when I disconnected the HDMI lead to the TV. This was more worrisome, as if the TV turned out to have a bad earth it would be expensive to get sorted out. Then I came across this handy post from CNET where the author suggests removing all your external coax/aerial connections.. voila! I removed our shared building aerial from the TV and the hum went away. Perfect. So now all we have to do is properly earth the aerial where it comes into our flat and the problem is solved for good. In the meantime though, removing the aerial so I can enjoy Inception in its full glory is a pretty easy workaround. Gotta love easy workarounds in the tech world. Of course this may not be the solution to your home speaker hum problem, but the main lesson here is isolate all possible causes in true Sherlock Holmes fashion, then you should be left with the culprit.

Recently Skype, the wunderkind of the cheap internet phone service (until Google Voice is global), rolled out Skype to Go numbers for all of their paid subscription members. The Skype to Go number is a phone number you can call from your assigned mobile phone to make, generally cheaper, calls abroad when you aren’t near an Internet connection. So not as cheap as calling abroad from Skype on your computer, but pretty handy nonetheless, especially when you’re using an iPhone and you can’t use the handy Skype App to call because there’s no available wireless.

The Skype to Go number is a local number, and consequently will be included within your phone plan’s normal monthly minute allowance. For most of us with OTT monthly plans this means an effectively free outbound call, with just Skype charges to pay for connecting to the other end. Just call the Skype to Go number, then type in the number you want to call (’00′ + the countr code, then the number) followed by a hash, and voila! Of course the trouble is that there is not yet a handy Skype to Go app, or extension to the Skype app, that lets you easily call any contact in your address book, which means typing in numbers from memory is an old skool skill most of us have lost.

There is a handy workaround though for numbers you call abroad regularly. Simply create a new ‘Skype to Go’ number on that contact, and cut and paste your Skype to Go number into the field, followed by two pauses (press the ‘+*#’ button to see that option), then the person’s international number, and don’t forget that final ‘#’. Save the number, then give it a go. You should hear the polite Skype voice saying ‘Please dial your number’ and then shortly after your phone will magically start to type in the number and off you go.

This is a life saver, but not the only option. You can also use one of the many card calling apps on the iPhone and set up your Skype to Go number as a card there. The only issue I’ve found with this approach is that for some security reason iPhone apps aren’t allowed to embed the ‘#’ character when they make a call, which means you’ll have to manually press the ‘#’ key after the app initiates the call. For someone with a lot of international contacts to call this might be a preferred option.

CXO magazine this month has an interview with John Linwood, CTO at the BBC, about the amazing success of the iPlayer, the BBC’s on-demand video service. You can only read the interview in their print magazine at present, however they do give us a great infographic showing iPlayer usage patterns.

The iPlayer has demonstrated the desire of people across the UK to access on demand content, and has simultaneously raised the ire of broadband providers who’ve seen download levels rocket. The iPlayer infrastructure vends 12.5Gb/second of pre-processed video to the many different players it supports - from mobile phones, through computers to the mainstream satellite providers who then help distribute the data themselves. Arguably the BBC is in a unique position around the world, being funded by public money which means that the content is effectively ‘owned’ by the British public already. Whatever the reason though, you can’t demand the success of the venture from a technology perspective.

[From The Next Web]

At the Tent London show during last week’s London Design Festival we came across the wonderful Wattson, produced by DIY Kyoto. The Wattson is a device for tracking and visualising your household or business electricity use, a great example of ambient feedback that we’ve touched on before.

The Wattson shows you either a gentle blue glow to indicate that your household electricity usage is reasonable, or a choice of kilowatts or pounds spent over a year based on your current electricity consumption. The yearly figure is a great way to inject fear into your wallet and encourage reduced electricity consumption, so much so that DIY Kyoto are seeing 20% reductions in electricity usage amongst users of their Holmes software who sign up to their website. That’s a great achievement, and all the better for being achieved by the carrot of positive feedback rather than the stick of fines and taxes.

The Wattson we bought at the show is a lovely piece of engineering, from a team of product engineers part funded by NESTA (a non-government body that funds creative innovation - in full disclosure I did use to work for them). The unit works by attaching round the main electric wire that comes into your house or flat, and then transmitting a signal to the main Wattson box that sits, visibly, in your living room. The transmitter is powered by four AA batteries (supplied) and the display unit has a charger, or can be powered by the USB connector through which you can also connect to the free software to review your consumption (figures are stored in the Wattson for the last 4 weeks).

This is all very exciting and I’m looking forward to getting ours working.. the only problem right now is that the standard transmitter connector only goes round standard electrical wires and our flat has a shielding, thick cable going straight into a junction box! The Wattson website rightly advises that you employ a professional electrician in these situations. So you’ll have to wait a bit longer for some proper feedback on how it works in practice. In the meantime we’ll just keep turning off lights and un-plugging our TV without knowing which activity is really having the most impact.