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TiVo has just released a “TiVo Branded” 802.11g wireless network adaptor aimed at Series2 owners. (compatible with 802.11b) This network adaptor enables users to use TiVo To Go (TTG), Multi-Room viewing, Music and Photo sharing, and Online Scheduling. This unit will cost $49.99 if purchased through TiVo. There are plenty of other units that offer same results, but are much cheaper such as Linksys or Netgear adaptors. (TiVo’s unit, however, ensures compatibility) Unfortunatley if you purchase this unit it will not function with PCs or Macs, just TiVos. Therefore, the advantage of purchasing 3rd party devices enables using the adaptor with units other than just TiVos (and is usually cheaper). Either way a 3rd party Wireless Router will be required for this to actually function unless you are only using your TiVo for local file sharing and multi room viewing.
Links: TiVo Gear | Linksys | Netgear
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Unlike other adapters, this one offloads some processing for the Tivo box, so transfers should be faster.