A handheld digital TV is a portable device which allows users to receive digital broadcasts. This can offer users many more channels than a portable analog TV, usually with better picture quality. However, using such a device on the move can mean much more retuning to get a signal than with an analog set. The decoding necessary to display a digital signal can mean such devices use more power than older handheld TVs.
The handheld digital TV became much more prominent in June 2009 when the United States switched off most of its analog TV signals. An estimated eight million people owned a handheld analog TV at this time. However, these devices became largely useless, as it was impractical to add a converter box in the same way as was done with full-size TV sets.
In most countries, there is a special standard for digital broadcasts for handheld devices. This is because standard digital TV decoders are designed for fixed aerials in locations with little interference. Handheld TV sets are often changing location when users are on the move, and are more likely to be close to other portable devices such as cellphones and computers running wireless Internet. In the United States, this standard is called ATSC-M/H, which standards for Advanced Television Systems Committee – Mobile/Handheld and is a variation on the ATSC standard used for full-size TVs.
Broadcasters which have an ATSC license are automatically covered for ATSC-M/H broadcasting in the relevant area. The signals for ATSC-M/H can be broadcast as part of the main digital television signal. The system also allows broadcasters to add special content for handheld TV viewers, including encrypted premium services.
An alternative to a handheld digital TV is to receive TV signals through a cell phone. This saves the need to carry around a separate device. Depending on the cell phone network provider, picking up TV signals in this way can give you access to satellite and cable channels which are not available through standard over-the-air digital broadcasting such as that used by a handheld digital TV.
However, receiving TV programming on a cellphone puts the viewer at the mercy of network coverage, which can be weaker than TV signal coverage. It can also be a pricey option, both for the data use and for any separate subscription fee you may have to pay. Similar technology, with similar advantages and drawbacks, is available for laptop computers, usually with a combined aerial and decoder built in to a small device which slots into a USB socket.