Freeview Playback is not new. These boxes that double as personal video recorders (PVRs) have been around for a good few years and the Freeview platform's organisers are hoping that the new 'Playback' branding does its job.

It's not clear why this box hasn't been called 'Freeview Plus', as it's obviously modelled on the success of the SkyPlus box, but we suppose it's because the 'Plus' may have suggested some add-on services.

The actual channels and content you can watch on Freeview stays exactly the same, so buying a Freeview Playback box will simply liberate you from the restrictions imposed by the TV schedulers.

Yup, there's no such thing as a free launch - Freeview channels may be free, but the first Playback boxes to have hit the market this summer have been quite expensive. So far we've seen a few from the likes of Sony, Humax and TVonics, with many more to come.

Any set-top box sporting a Freeview Playback badge is basically a digital TV recorder. With at least two Freeview tuners inside, each box has to meet certain quite stringent criteria to ensure consumers get the best deal.

Every Freeview Playback box must include an eight-day electronic programme guide (EPG), scoring one over SkyHD's seven-day guide. In practice, the accuracy of any EPG depends on information provided by broadcasters, which is the main reason why a 14-day EPG has never found favour with PVRs.

The easiest way to describe how a Freeview Playback box works is to talk about those specific models.

Having already garnered great reviews, the Humax PVR9200T is perhaps the most ambitious box.

It sports a 160GB hard-disk drive that's capable of recording around 80hr (2GB equals one hour) of both TV and radio. Its two Freeview tuners allow you to record one channel and watch another or record two channels simultaneously and watch something else you've recorded previously to the hard disk drive - and all for £200.

Unlike Humax's fairly standard set-top box design, the £190 TVonics DVR-FP250 is a smaller and glossier affair. As well as having a 250GB hard disk, its real advantage is that it's one of the most environmentally friendly digital TV recorders on the market, using 3.5W in standby mode (compare that to an industry average of 11W, and 14.5W when in full operation - 28W is normal).

Lastly, there's Sony's RDR-HXD560. Costing £300, this box only has a 80GB hard disk (40hrs of recordings) and just one Freeview tuner, although you can still record one live show while watching a previously recorded programme.

So far, so basic, but there are some niceties here such as a series link: select EastEnders on the TV schedules, hit the series link button, and every subsequent episode will be recorded. Sony is charging an extra £100 because the RDR-HXD560 also has a DVD recorder that can fit about eight hours of TV recordings to a DVD+R double layer disc and is great for archiving.

All three can receive over 40 free digital TV channels and, as a great replacement for a VCR, these Freeview Playback boxes could be the future, but only if the idea can be standardised and perfected. So far, Humax's offering seems to be the best option around, but we expect many others to follow, including Alba, LG and Sharp, in the run up to Christmas.