are broadcast in 1080i format (though the box can be set to scale this to 720p if the user wishes), using the H.264/MPEG-4 AVC compression standard, from Astra 2A, Astra 2E, Astra 2F and Eutelsat 28A satellites at 28.2°E and 28.5°E in a new DVB transmission standard, DVB-S2. BBC HD was initially broadcast using DVB-S but switched to DVB-S2 on 6 June 2011. The Version 5 EPG (electronic program guide) is almost identical to the one found on Sky+, with the exception being that by pressing TV Guide and then number 2 on the remote control, listings for only the HD channels are shown. An update was sent to the HD boxes early on 20 March 2007, which also included code for Sky Anytime (now OnDemand). Version 8 of the Sky Guide, dubbed the Sky+ HD guide, included a Mini TV, improved search functions and a refreshed interface. On 1 October 2010, Sky began the process of downloading open-source software to Sky+ HD receivers. Unlike the majority of software upgrades made by Sky, the open source licences require Sky to notify customers that the download has taken place. Subscribers are notified with an on-screen message that refers them to a dedicated section of the Sky website. The website also includes a download of the open source components including the building environment. Sky says that it has found a number of Open Source Software developments that provide capabilities that benefit the software used in the Sky+ HD box. Release history Below is a list of boxes that have been manufactured for use with Sky+ HD. All boxes are now discontinued and no newer models are expected, since the launch of Sky Q. Sky also manufactured a standard Sky HD box without a hard drive, aimed primarily at customers subscribing to Sky Multiroom, as a cheaper alternative to receive HD channels if record and playback were not required. Developments Increase in HD channels In over three years since launch, the number of HD channels available has increased significantly, thus Sky+ HD is the world's largest HD offering outside North America. Sky brought an update to its Sky+ app, this features a similar looking design to the Sky+HD box bringing the services more in line with one another. On 30 July 2009, Sky confirmed the launch of a "pull" video-on-demand (VOD) service for 2010, adding to the current Sky Anytime "push" VOD service.