As a result of the North American digital switchover, tuner-equipped devices manufactured or imported into the United States are now required by the US Federal Communications Commission to include digital tuners.
This has caused most new VHS recorders to be implemented as DVD/VCR combo units, or to be manufactured without tuners. The US requirement of ATSC compatibility forces inclusion of MPEG-2 decoding hardware, which is already part of all DVD players but which otherwise would not have been needed in an analog-only VCR.
An ATSC-capable DVD unit can also serve as a more-powerful alternative to digital television adapters, which allow DTV reception with older NTSC analog televisions. The DVD recorders offer additional capabilities, such as automated VCR-style timeshifting of programming and a variety of output formats, that are deliberately not included in the most common mass-market US ATSC converters.
Unlike the more common digital television adapter boxes, DVD recorder units are able to tune both analog and digital signals - an advantage when receiving low-power television and foreign signals. Some, however, do suffer from many of the same design limitations as the less costly converter boxes, including poorly-designed signal strength meters, incomplete display of broadcast program information, incompatibility with antenna rotators or CEA-909 smart antennas and inability to add digital channels without wiping out all existing channels and rescanning the entire band. A DVD recording of an over-the-air HDTV broadcast is at DVD resolution, which is inferior to the original broadcast with 720p or 1080i resolution. Some units also provide limited USB or flash memory interface capability, often only supporting viewing of digital camera still photos or playback of MP3's with no ability to write video to these media.
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