Monday, 28 September 2009

Getting ready for the National TV Retune

Tesco, alongside other TV retailers, is getting ready for customer calls on and after 30th September.

That date is called, in a rather community-spirited manner, the National TV Retune. It's where customers who receive digital channels through their aerial - Freeview - suddenly stop receiving a whole load of them and have to enter their Freeview receiver's setup menu to perform the retune.

The reason for the National TV Retune is that Freeview - that is, the UK's digital terrestrial (ground- based) television service - is an evolving system and a great deal of technical shifting around of TV and radio channels is required to:
  1. Allow Channel 5 ('Five') to be received everywhere on Freeview. This is a legal requirement as 'Five' is a public service broadcaster (PSB) like the BBC, ITV and Channel 4. As a PSB, Five is granted the right to be received everywhere digitally by Act of Parliament. It's important - whole swathes of the nation have missed out on its launch by the Spice Girls in 1997 and its evolution from original 'stripped and stranded' schedule to the very competent fairly upmarket format broadcast today.
  2. Empty one of the signal multiplexes completely so it can be re-calibrated to the new DVB-S2 format to support future HD channels (huzzah!). The existing channels on that multiplex (called 'Multiplex B') will be moved to some of the other 5 multiplexes which will themselves be re-calibrated to support them - and in the process make redundant a lot of old Freeview equipment.
  3. Take the channel information data (called the 'Network Information Table' or 'NIT' - the source of data that provides the channel line-up) , and split it into two because one can't support many more channels - and in the process make redundant a load more old Freeview equipment.
The re-calibrated multiplexes are more 'complex' in their make-up than before in order to carry the extra channels. I won't go into here because if I say Coded Orthogonal Frequency Division Multiplex (COFDM) you'll probably stop reading!

Let's just say that these signals need to be picked up more cleanly (and more strongly) so some customers with doddery old TV aerials that nevertheless picked up Freeview will probably find the service less reliable.

Some old Freeview equipment won't understand the re-calibrated signals so won't be able to receive them anyway. Add to that the splitting of the channel information data ('NIT') and it means that, on these boxes, whole swathes of channels will simply disappear. Now that will generate phone calls!

Some customers who pick up Freeview channels today on a relay station will actually lose some channels. So its goodbye to Poirot and other ITV gems unless you point your aerial to a main transmitter rather than a relay (if you can) to continue picking up ITV3 and ITV4.

I hope you're getting my message; it's all a bit of a mess which we (Tesco and others) have to mop up. As a technologist of course I understand why it's happening, and I know it is all for the future good.

The trouble is that Freeview is chosen by the least tech-savvy of the nation. After all if you're "into" TV then you'll have Sky or Freesat - and both Sky and Freesat offer automated updates of the channel line-up.

Freeview viewers do get a great channel line-up so it's certainly worth having over analogue - even my 96-year old Gran has it. She lives in Bournemouth and is an "old Tory" who is looking forward to watching the live Conservative Conference next week on channel 81, bless her.

Despite living most of her life with zero, then one, then two TV channels, she loves Freeview as she enjoys her politics and is hooked on the BBC Parliament channel.

Unless my Mum can work out how to retune her TV (with me on the phone if necessary) then Gran hasn't a hope of watching.

Tesco is standing by to help our other customers.

On the official Tesco iPhone Application and some developer disquiet.

A recent article concerning the Tesco API appeared in Computing magazine on 22 September 2009 telling of some developers being unhappy at our plans to have our own iPhone application for grocery in the Apple App Store.

One paragraph in the article quoted an anoymous developer who apparently said,
“Tesco has just taken a big dump on our heads by announcing the creation of an official iPhone app for Tesco,” said one developer, who wrote to Computing on condition of anonymity.
“I don’t know how many other developers were looking at iPhone solutions but I was certainly one of them. Fortunately I had only invested about 20 hours so far in a project I expected to take 400-600 hours, but I think Tesco has sent a clear message to developers that as soon as a market looks like it might have mass appeal they intend to stomp all over the little guys by writing an official app of their own. That is not how to foster creativity with an experimental new API.”

Despite the robust language of the developer, and bemused concern that he demanded anonymity (in case I go round his house and 'request' our Tesco Direct catalogue back?), I certainly empathise with his view.

But I also disagree.

First of all, applications of this new genre follow the principles of evolution by natural selection - each new application takes all the good bits - and dumps the bad bits - of previous incarnations, evolving as new ideas come into focus, and following popular ideas.

A good example is the evolution of Twitter clients - each application has evolved and extended the Twitter system way beyond its original design. I'm on my third iPhone Twitter client (Twitterific) because it has more facilities than previous clients and is easy to use.

I hope the same happens with our iPhone grocery application. Yes it will be good, if basic, but I encourage third parties to take its best bits and go forward.

Secondly, if I denied anyone in from writing an iPhone application (or for any platform for that matter) what message would it send to our staff? That they are forbidden from spending time working with this form of innovation? If that message got out we would get a worthy exodus from of the most innovative of my colleagues and a total inability to recruit anyone.

In IT I am working with the leadership team to foster innovation – indeed we have our own embryonic IT Innovation Club up and running, and colleagues can spend both their own time and some business hours on R&D projects that they wish to try out. It’s from this source that our first iPhone ‘Store Finder’ application has been created. is a great place to work but not everyone thinks of us first when considering an exciting future in IT. The IT Innovation Club is my overt part in changing that external attitude. If that means we have applications from our developers in our name (and theirs of course) alongside applications of third party developers, so be it.

Monday, 21 September 2009

Important API Updates: Dev Portal moved; Azure tear-down ready for beta API

Dear API Developer

There are some important updates to the Tesco API and the developer portal that have occurred today, and there is action you must take to keep your client application running against the community technical preview edition of the API.

Developer Portal Moved
The API developer portal, where you manage your developer & application keys, and consult the online API documentation has moved to its new home at where your developer account and keys are now stored.

The developer portal is now at:

(You can also type in whereupon you will be auto redirected to the secure web address).

The developer portal at is now shut down and soon all of will be completely shut down as applications are transferred to the domain.

Don’t use Azure from now until Beta API is ready
We’re going through the process of re-equipping our space on the Microsoft Azure cloud computing platform ready for the new beta API. On Wednesday 23rd September the community technical preview API hosted there will be torn down so we can start uploading the daily beta builds to the Azure space. If you followed the online documentation to move the endpoint from or to the domain, now you will have to move it back to Sorry!

The community technical preview API will still run at: where it will live until the final customer has been moved over to the Martini platform in the coming next few weeks.

Beta API dev progressing
Finally we are ploughing through the API development that will run the service on top of the new Martini platform. More news as we progress coming soon!

All the best
Nick Lansley
Head of R&D

Friday, 18 September 2009

Letter of Rejection

So I come back from holiday to uncover that the R&D team’s first iPhone application to be submitted to the Apple App Store has been rejected!

The letter of rejection was pleasant and helpful, detailing a user-interface reason for the rejection and looking forward to a rapid re-submission.

The R&D 'Store Finder' application, which allows iPhone users to locate their nearest Tesco branch, had a problem if the user denied it access to iPhone’s location service so it could not obtain the current latitude and longitude of the phone.

Basically it had been accidentally programmed to have the same attitude as an affronted celebrity denied access to a posh night club (“Don’t you know who I am?”) then give them a ‘stores near me’ list anyway by assuming they were actually located at HQ in Welwyn Garden City!

It’s a minor change (disable the ‘Stores Near Me’ button and switch to the ‘Town/City Search’ screen) so I have to thank the App Store team for their detailed response and their encouraging tone.

It’s no discredit to the developer either - the brief was that the application had to get the customer quickly to the store, so denying the application access to the current location and having to perform a manual search will make the it considerably less ‘immediately’ useful.

It’s some time since I’ve had a letter of rejection so today I will pin it to my local office noticeboard under one of the written tenets of research: “Go Wrong Quickly and you’ll Learn Quickly”.

Friday, 4 September 2009

Fake email phishing for Tesco usernames and password - ignore!

It may be a poor attempt at phishing but look out for this email message and delete it. Mine came from "Tesco Webmaster" but there may be other email sources. The perpetrator may be trying to snag a Tesco email account to make future phishing emails look more authentic. Help me make sure his/her failure is complete.

----Tesco Webmail Technical Services-----

Account Subscriber,

We are currently performing maintenance on our Digital webmail Server to improve the spam filter services in our webmail systems for better online services to avoid virus and spam mails. In order to ensure you do not experience service interruption, respond to this email immediately and enter your Username/id here (********) password here (********) and future password here (********). Checkout new features and enhancements with our newly improved and secured webmail.

NB: We require your username and password for Identification purpose only.

----Copyright © 1997-2009 Tesco!. All rights reserved-----