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A little orange wire..

The quality of Internet in our house has been dubious to say the least for some time and we've long associated it with poor street cabling and distance from the exchange.  It is also made worse by bad weather (rain, usually) so we were putting up with the poor performance as being beyond our control. Recently, however, the service had become very frustrating prompting me to investigate further. The symptoms vary, but the usual ones are:
  • Long delays waiting for the browser to start downloading a page
  • Pauses when clicking on a link for the new link to start
  • Page loads taking a long time
What was (slightly) odd was that these delays did not seem to be restricted to the evening (the traditional Internet 'slow time' in the UK). They were occuring throughout the day - even in the quiet times in the early morning.

Brief Investigation
The first thing I did was to look at our ADSL router, a third-generation NetGear DG834G.  There seemed to be no errors on the set up of the router - I even rebooted it to see if it had got itself confused - but it was when I looked at the router statistics that I saw the seriousness of the problem:


The figure that set my alarm bells ringing was the Downstream Noise Margin, showing here as 2dB but regularly this figure was flitting between 0dB, 1dB and 2dB.  That's bad!  Noise Margin is a measure of how much headroom the router has to maintain a good quality ADSL connection and according to these statistics my router doesn't have any!!
 
Noise Margins and Signal to Noise Ratios
Let me try to explain this.  Your broadband ADSL service is delivered from the exchange by a piece of equipment called a DSLAM which works by putting a signal onto the phone line to your house.  Your router needs to reliably decode this signal so that it can link you to the Internet.  If there is noise on the phone line this signal will be degraded and your router will have difficulty decoding it.  The impact of this is that the quality and speed of your broadband ADSL will suffer.  The more noise; the more your service will suffer.  You can probably see then that the ratio of your ADSL signal level to the phone line noise level can be used to measure the quality of your ADSL service.  This ratio is well-known in communication systems engineering and is referred to as the signal-to-noise ratio or SNR.  The higher the SNR is; the better your signal is and therefore the better your service will be.  As a good analogy, think of yourself trying to listen to your friend talk to you at a football match or in a loud pub.  It's very difficult to hear every word he says unless you listen very hard or if your friend shouts.  This is a situation where there is a very poor SNR.  Now imagine your friend talking to you in a coffee shop or a restaurant.  You would expect to have no problems hearing everything that your friend says.  This is a situation where there is a reasonably good SNR.

Signal to Noise ratio or SNR is a term used to describe the ratio of wanted signal strength to that of unwanted noise levels and is measured in units called dB (decibels).  This is a logarithmic scale where each 3dB of SNR doubles the ratio of signal to noise.  For example, if the noise level was about 1/100th of the level of the signal then the SNR would be 20dB.  If we double the level of noise, the SNR would decrease to 17dB.  However, if we increase the signal to 1000x the level of the noise the SNR would increase to 30dB.  More info can be found here

Having established what SNR is, we can now introduce the Noise Margin.  This is a sort of buffer zone on top of the SNR that allows the router to cope with all the variations in noise levels that occur through the day.  On a 'good' ADSL line this figure is usually around 6dB. So, with our Noise Margin being measured as 0dB to 2dB, our Broadband router had no headroom and that from time to time the level of noise would increase to a level that affected our service.  Indeed, it is perhaps a wonder that our ADSL was working at all - never mind with the poor performance we were experiencing.  Just goes to show that the NetGear hangs on to that signal in the noisiest of environments!


Further Investigation
So now we know what the poor performance is caused by - it's too much noise or interference - the next steps are to try to understand what's causing the noise and then to attempt to correct it.  As usual, you begin with a couple of searches on a search engine and I was fortunate to quickly find the excellent kitz.co.uk that in their own words ... "contains a wealth of adsl information such as how adsl broadband works".  On that site I found a section devoted to poor noise and the likely causes. On this site was a page dedicated to 'Low SNR problems' and this page has a wealth of details I could step through.  I worked through the steps that are listed and came upon "~ One last trick - remove the ringwire." The 'ringwire' is a left over from days gone by when it was used to supply the ringing current to older phones.  Most modern phones don't need this wire and in modern installations it can actually be removed as all it does is act as an antenna for electrical noise.


Here you can see our incoming NTE5 faceplate with the front cover unscrewed and the orange/white wire disconnected from the faceplate connector pin 3.  The blue/white (pin 2) and white/blue (pin 5) wires are NOT touched.  (Note that in some installations you may have a white/orange wire on pin 4.  This can be removed also.)


Result!
Having done this and re-assembled the faceplate the internet router was rebooted and immediately the following router statistics were recorded:

Note how much better the noise margin is.  Note also how much greater the connection speed is.  Just disconnecting this single orange wire has improved our download speed by 14%  And the problems we've had since then have largely disappeared.

Now to tune the MTU - but that's a subject for another time.

Happy Surfing!

Seeing clearly to drive.

This time of year is very difficult for drivers with humid air, changing temperatures, mist, fog and low sun.  All of these work together to make driving both hazardous and stressful.  2011 is different, because on top of all this we now have overbright DRLs adding a further element of distraction and danger (you can learn more about these on Lightmare's site or on my previous post).  If roads are damp and covered with leaves you are further increasing the risk of a coming together as your braking distance is greatly increased and you are more likely to skid when braking.  Indeed, statistics show that there are 15 per cent more accidents in October compared to the monthly average for the previous six months, with 21 per cent more accidents that in August alone.  (see this Telegraph link).

While you cannot get rid of all of these distractions and dangers you can at least minimise their impact on yourself and others and significantly reduce the risk of an accident by making sure you can see clearly through the windscreen and by checking that your vehicle is serviced and roadworthy before the autumn (at least check your tyres, lights, brakes and battery).

Before you set off on any journey you should make sure you can see clearly to drive.  If your windscreen is at all greasy or just damp with condensation, your vision will be distorted and glare will be increased, either of which will greatly reduce your ability to differentiate between that parked car, that oncoming car with all its lights on and that pedestrian behind the car crossing the road.  How many times do you enter such scenarios effectively blind to what's in front?  It doesn't bear thinking about, does it?

Cleaning your windscreen
So how do you clean your windscreen effectvely?  Believe it or not, newspaper and vinegar are your friends here.  Simply use white vinegar and water in a 1 to 10 mix, applied and polished with newspaper (carefully avoiding surrounding paint and brightwork) and your windscreen should become grease-free in a few minutes.  Use a cloth soaked in the same mixture and do the wiper blades at the same time, as these get greasy too.  You should be able to polish the screen afterwards with a clean dry piece of newspaper to finish off.  Don't use wasing up liquid - this will leave a residue on the screen that will very quickly gather up more road grime and will reduce your vision again.  Don't forget the inside of the screen too as this can also get as greasy (the moisture in your breath, your hands wiping the screen and - worst of all - tar from cigarettes if you smoke).  Don't forget to check the screenwash and make sure it is full (use proper screenwash - not washing up liquid!) and the nozzles adjusted. Finally, make sure you have a kit for the inside of the car. A clean microfibre cloth, a window wiper/scraper and a means of de-icing)

Driving in poor conditions
While driving when it is humid, drizzly and foggy or when the temperature starts to drop, remember to set the heater controls to recycle the air, rather than to bring colder, damp air into the car and letting it condense on the windows for you.  If your car has air conditioning, use that - even if the temperature is set higher, as the air conditioner also acts as a dehumidifier, effectively drying the air in the vehicle.  All of this helps keep the windscreen clear and your visibility as good as it can be for your journey.  The less glare on yourscreen, the clearer your vision and the less impact oncoming lights will have on your driving. Finally, don't forget your glasses.  Keeping these clean will reduce the glare too.

Drive safe, drive considerately. Don't use lights inappropriately. Be courteous to other road users.

Happy motoring!

Eight tips to watch for if you water-damage your Smartphone

The Tale of woe

So I went swimming in the sea while I was on holiday.  We've all done it, many times.  What was different this time was that my Smartphone went swimming too.  Not by design and not through choice.  A moment's distraction, a splash and it was all over.  Thing is: I didn't realise it was in my pocket until about 15 minutes later, by which time I'd been snorkelling and the phone had completely drowned.
As soon as I realised the phone was in my pocket, I got out, took the phone apart and took the battery out.  Then I rinsed it with the fresh water from my water bottle and dried it in the sun.  I went to town later on and even bought a set of small screwdrivers so I could dismantle the phone and rinse and dry it out properly.  As it was the first time I had dismantled my phone I looked on the Internet for instructions and soon the phone was in bits in a shallow dish being gently rinsed and cleaned with a toothbrush then dried carefully leaving the phone overnight to dry completely.

After re-assembling the phone I popped the battery in, not expecting much, and sure enough the phone remained as dead as a dodo. Not even a flicker of life. Not looking good.  I was fortunate in that my good lady wife has the same phone, so I tested my battery in her phone - it was fine - and testing her battery in my phone confirmed that my phone was still dead.  (Apple users can't easily do this as Apple have made their phones without a battery cover).  So that was that. With the phone looking dead I carefully put it to one side and got on with the holiday resolving to have another look when I got home.

The Long Wait
Holiday over, all safely home and taking stock of the situation:
  • Can I get the phone working now I'm home with all my kit around me? Answer: No.  Phone still inoperative despite further cleaning and probing with alcohol and swabs
  • Have I another phone I can use in the meantime? Answer: Yes.  My old 2006 vintage Sony Ericsson K800i
  • Can I live without a Smartphone? Answer Looks like I'm about to find out... :o(
  • What are the arrangements with the Travel Insurance - am I covered and with which policy?

First things first. I transferred my SIM to the K800i, charged it and turned it on.  Success! Welcome to Orange.  I'm back on the air.  Next, insurance.  We had ceased the phone-specific insurance within the first month of owning the phone, so we now had two avenues for cover here - our Travel insurance and our Household Contents insurance.    After ringing both firms and discussing the matter with them, we found that the Household Policy covered the phone but with a £200 excess and I lose a 10% NCB.  I was assured this was a Good Deal.  I disagreed.

I then spoke with Nationwide, as one benefit of our bank account is that it comes with free Travel Insurance.  They were a lot more helpful, and sent me the forms I needed to complete so they could assess my claim.  Quite rightly they wanted to know:
  • Did I really own the phone?
  • Was I really on holiday at the time?
  • Was it really damaged and beyond economical repair?
  • Was there any other insurance for the phone?
  • What was the likely cost of replacement?
The Damaged Repair
All of these were easy to answer - except that for the 'damaged beyond economical repair' I needed a report from a recognised repair company that confirmed the status of the phone. Easy, I thought.  Just take the phone to an Orange Shop. Nope.  "We don't do repairs, sir, we'd have to send it to HTC"  This seemed to be the consistent story for all the high-street shops regarding repairs.  So, using the Power of the Internet, I located a M Blue Ltd in Essex who "are highly experienced in water damage repairs". The cost? £34.99 including return delivery.  This looked fine.  The process would take three days and I would get a repaired phone or a report back that confirms the phone is irreperable.  So I sent the phone off to them, wrapped and protected - and complete - and then I waited for the report.  Their service was quick and their communication excellent.  It's just a shame that they did not take proper care of the phone while it was with them.  It was returned with two parts of the case broken, two screws missing and not properly assembled.  I sent them photographs of the phone as it arrived back to complain about their lack of care and these are included below:
Their reply?
"It is clear from your order submission that the device has been opened before sending it to us and on arrival we have found it to be in a rough state. Our technicians are trained to repair to a high standard and not to damage devices in the way you claim."

Now I know this is not true, but it's my word against theirs.  The phone was sent to them water damaged but physically complete and sound.  It was returned with further damage to the case showing a lack of care on the part of their engineers. My worry - which was expressed to them - was that their poor quality of care and workmanship would be reflected in all their repairs, so on that basis I cannot recommend this company at all for your phone repairs.  Instead, I do recommend that if you have to return your phone for repair, you take a photo of your phone alongside the box you use to send off the phone and include a print of the photo in with the parcel as you send it off.  This way, you stand a better chance of arguing your case if they do not take care of the device.

Back to the insurance claim.  This took a long time to settle, partially because the insurance company were "just starting to use a new system" and were "busier than normal" (these do seem to be stock excuses!!) but if you've not heard anything from them, ring them weekly, note the details of the call (because they will do the same) and try to see if you can hurry things along.

One thing to watch for is if the insurance company need to check something with another company.  The odds are that if Insurance Company A need to check something with Company B, Company B will not be able to give information about you to Insurance Company A because of the Data Protection Act.  If this is the case, find out what the Insurance Company want, agree that you'll ask for it and how you'll supply it, and get it yourself.  However, realise that even with all the chasing in the world, it still takes too long to process a claim.  I started my claim for the water-damaged phone in September, when I returned from holiday and finally got a settlement in November.

Top Tips:
  1. Make sure you make a point of putting your phone safely in your belongings when you go swimming - or better still don't take it to the beach at all
  2. If your phone gets soaked like this, turn it off. Take out the battery as soon as you can. Disconnecting the battery stops any electrical currents going where they shouldn't and protects the phone from further damage.
  3. Cleaning. Dismantle the phone - carefully - and then clean out all the salt from the sea as gently as you can.  Ideally you should use iso-propyl alcohol as this is the cleanest cleaner you can get, but this is not always possible.  Equally important is to dry the phone thoroughly but gently so that all traces of moisture are removed.  Drying involves three stages.  Stage 1 is blotting all parts with a paper towel or tissue, stage 2 is gentle heat from a hair dryer or similar and finally (if necessary) stage 3 is to store the phone components overnight in a sealed container with a desiccant such as silica gel or uncooked rice.
  4. Always have a spare working phone somewhere available - just in case.
  5. Always be sure what your insurance polices provide in the way of cover for your smartphone - you may not need to take out insurance when you buy a new phone, but you should satisfy yourself that the cover you've got is the cover you need.
  6. If you're sending your phone to be repaired, take a photo of it as you send it to record its state as sent for repair.
  7. Make a note of all calls you make, when they were made, who you spoke to and what was discussed - including the state of the claim.
  8. Help the Insurance Company get hold of information if they need it.  It hurries things along.

Charging my iPod's discharged battery

I have an old and venerable 30G iPod Gen 5 which has served me well for a few years.  It's had a new battery, a new logic board and a new rotary switch, but it works fine.  Until a week ago, when I switched it on and it didn't respond.  The battery was flat, so I plugged it into the charger and waited overnight.  Then I left it a whole week.  The battery remained uncharged - even after a week of being connected to its charger!

Now I have noticed on previous occasions that the iPod will deep-discharge the battery if it is left unused too long and then not even a normal USB charger will rescue it.  Until recently, I have been able to get round this by using the iPod interface on my Becker car radio, which always seemed to be able to wake up the iPod and charge it.  But I've changed the radio in my car now and the new one doesn't do quite the same job.  So.  Do I just replace the iPod battery or do I look to try and charge the iPod some other way?  Being reluctant to give up on a technical problem I chose to try to charge the unit another way - after all, if the Becker could do it so should another charger - if it charges the same way and, what have I got to lose?

The Becker iPod interface is not based on USB, so its design is not constrained by the specifications of USB.  I therefore suspect that it is capable of providing more power to the iPod than a USB port and therefore has more chance of getting the charging circuit in the iPod to start charging a deeply discharged battery.  Since, by now, a number of laptops and chargers had been tried and failed to charge my iPod I had a look on the Internet to see what else I could learn.

I rapidly found that the specification for USB power was that the USB voltage is nominally 5v (more specifically, no more than 5.25 V and no less than 4.75 V (i.e 5V±5%)).  A USB outlet should also be capable of providing upto 500mA too.  So I knocked up a charging circuit based on my bench power supply, an old USB lead and a digital voltmeter.  I then put 5V across the power leads of the USB cable and connected the iPod lead between the power source an the iPod.  Guess what?  It didn't charge the battery!  So I carefully adjusted the voltage of the power supply until it read 5.25V.  Still no charge.  Perhaps my battery was dead after all!



Back to searching the Internet.  It turns out that just supplying the power is not enough: there also has to be a signal to the unit being charged that charge is available and this was what was missing from my simple circuit.  Not one to give up lightly, I looked at the Internet again, this time looking for DIY USB chargers and chanced upon this indestructible project which seemed to answer my problems.  Turns out I was supplying the right voltage; I just wasn't turning the charging circuit on in the iPod.  It seems that the iPod looks for a voltage pattern between the two data leads to identify a valid, dormant USB port before turning on the charging circuit.  The indestructible says that you need four resistors arranged as a bridge so that 2.7V is present on D- and 2.0V is present on D+.  I set up four resistors on a breadboard and went to work.


And for those who want to know exactly what I connected up here is a schematic:


Once this was set up I switched on and plugged the iPod into the makeshift charger.  Within a few seconds I got a warning message on the iPod that the battery was very low - success!!  The iPod had woken up at last and was beginning to charge up..


Now I have enough juice in the iPod to bring it back to life, I have transferred the iPod to a proper charger and it is now charging merrily as I write this blog.

The morale of the story?  Well, there are three:
  • Don't let your iPod get as deeply discharged as I did mine
  • Don't assume that 'any old USB charger' will do - if one doesn't work, then try another.  Or try a computer.  Or another lead.
and
  • Don't assume that a dead iPod is a broken iPod.