A leaked memo to staff, posted on Cable Forum’s discussion boards, says monthly subscription will be £10 or £15 a month depending on which TV channels the customer subscribes to.

Installation of TVDrive, a technology ntl acquired along with Telewest earlier this year, will be free for new digital TV customers but existing customers wanting to upgrade will have to pay a £75 call out fee.

Existing customers can avoid the £75 one-off hit by opting to retain their existing set top box and connect it to a second TV elsewhere in their house, taking out a ‘second box’ subscription of £5 a month.

Whether a customer is new to digital TV or simply taking an upgrade, there will be no cost for the TVDrive set top box itself – a considerable saving over the rival Sky+ service, for which subscribers must buy a set top box priced at around £100.

ntl will not allow customers to have more than one TVDrive in their home.

The company has told staff that its existing Video On Demand (VOD) service will work differently for TVDrive customers but the leaked memo gives no further details of this.