In a bid to drive more retail sales, digital video recorder maker TiVo said Tuesday that it is offering a $150 mail-in rebate on its 40-hour set-top box, bringing the price to $49.99.

The move comes as TiVo’s main source of growth-satellite operator DirecTV-gets set to begin pushing a DVR from NDS Group, a TiVo rival that, like DirecTV, is controlled by Rupert Murdoch’s News Corp. It also sweetens a similar mail-in rebate offer announced about a year ago, in which retail buyers of TiVo boxes got $100 off the purchase price.

As part of the current promotion, TiVo is offering the rebate on 40-hour set-top boxes purchased before Nov. 27 and activated by Jan. 15, 2006.

TiVo’s owned subscriber base has long been just a slice of the company’s overall subscriber pool, which had reached 3.6 million by the end of July. In the second quarter alone, the company added 40,000 owned subscribers, versus 214,000 customer additions made through its partnership with DirecTV. A year ago TiVo added 63,000 owned subscribers.