Anyone who has ever used a USB DTV tuner stick and antenna to watch TV on a notebook knows that reception is fickle. It works when you’re still—just don’t expect to see much while repositioning the computer, or in a moving vehicle. Now, some DTV stations have begun allocating 3- to 4 megabits of their 19.4 Mbps allocation for reception by mobile handheld devices, including a new generation of USB stick tuners and portable TVs. Compatible smartphones and tablets are also anticipated. The broadcast service is referred to as ATSC-M/H (Mobile/Handheld) or simply, Mobile DTV.
A TV broadcaster can choose to simulcast programming from its main channel or embed a separate program stream. Since the Mobile Handheld channel is meant for screens as small as 3.5 inches, the resolution is decidedly non high def. But the signal is especially robust, with redundant bits meant for error correction. Also, reports suggest that changing the channel may take a few extra seconds because the system first builds a buffer to protect against fleeting interruptions.
Earlier-generation USB stick TV tuners and DTV portables are not equipped with the new Mobile Handheld technology, but a few products are just now becoming available even as more TV stations begin incorporating the Mobile DTV signal. Devices include the Hauppauge WinTV-Aero-m USB Mobile TV Tuner and Coby ATSC Digital Mobile TV USB Receiver.The two tuners are similar, but there are significant differences, too. Both require a Windows-based computer with an available USB port and a CD drive for software installation. Both include DVR software so you can record, time-shift and play over-the-air programs you receive in your computer.
The Hauppauge WinTV-Aero-m USB Mobile TV Tuner is a superset tuner that can receive standard definition, high definition and Mobile Handheld TV. So, assuming your computer’s screen has sufficient resolution to support a high-def picture, you’re in range of the TV station’s transmitter and you’re not in motion, you should be able to watch American Idol, the World Series or the Olympics on your computer as it’s being broadcast by your local TV affiliate. But if you are moving and the TV station has chosen to insert an MH simulcast in its broadcast signal, you may be able to continue watching the program, albeit at a lower resolution.
You may want to scale down the viewing window to preserve image crispness on a notebook with a 17.3-inch display but retain the window full-size on a 10-inch netbook. In the Hauppauge WinTV-Aero-m USB Mobile TV Tuner box are an adapter cable for adding an external antenna (a telescoping antenna is built into the USB stick/tuner), a credit card-size remote and a USB extender cable so that the tuner stick doesn’t block an adjacent USB port, as well as for providing flexibility with antenna placement.
The Coby ATSC Digital Mobile TV USB Receiver (DTV111) receives just Mobile TV broadcasts. So, even if you’re glued in place, you will not be able to watch standard DTV or high-definition broadcasts on the computer to which it is attached. The Coby comes with both a compact antenna and an auxiliary external antenna with base.
Because the Mobile DTV signals are freely available out of the air from commercial and public broadcasters, you don’t pay a subscription for broadband access or a fee to view a particular program. In the New York area, WNBC (NBC), WLNY (independent), WPXN (Ion TV), WNJU (Telemundo in Spanish) and WMBC (Korean, Chinese and Spanish programming) are already broadcasting Mobile DTV signals. Stations planning to begin service later this year include WNET and WWOR. For a list of stations around the country, see the Mobile DTV Station Guide.