PRODUCT REVIEW
OnAir Solution USB 2.0 HDTV-GT Receiver
Got a Windows laptop? That’s all you’ll need to watch DTV and HDTV on the road, thanks to the OnAir HDTV-GT receiver with USB interface. It’s got a 5th-generation 8VSB front end, too.
Although the market for discrete set-top boxes for terrestrial DTV reception has shrunk considerably over the years, there are dozens of “turn your computer into a TV set” plug-in boards and adapters available for reasonable prices. Unfortunately, some of these products resemble cable modems in size and weight.
While those aren’t too convenient for on-the-go reception, the OnAir HDTV-GT certainly is. Just plug it into your laptop’s USB 2.0 port, connect an antenna, and you’re ready to watch CSI or Dancing With The Stars in HD! This little box will tune NTSC, ATSC, and QAM signals, let you record and playback from your hard drive, and even analyze the MPEG streams from each DTV signal with optional software.
Figure 1. A front view of the OnAir HDTV-GT.
Figure 2. The back side.
OUT OF THE BOX
There’s not much to it. The HDTV-GT looks like a sleek, oversized computer mouse, finished in gloss black. There are only a couple of connections — a USB 2.0 port, an RCA connector for the antenna, and a multi-port input connector for connection to S-video and composite sources.
You’ll also get a small, collapsible whip antenna, a USB cable, and a remote control that’s actually bigger than the tuner module! Assuming you don’t need the remote or the AV cable on a trip, everything else can fit into your laptop case quite easily.
MENUS AND OPERATION
The hardest part of using this product is getting the drivers to install correctly. In my case, I was running Windows XP SP2 and repeatedly got a prompt telling me the drivers were unsigned by Windows. (No worries, the drivers are just fine!)
Unfortunately, each time you connect the OnAir HDTV-GT to a different USB port, you’ll be prompted to install the drivers again. Just remember which port you used the first time (my Acer laptop has four of them).
Once the driver is installed, you can plug in the receiver, connect an antenna, and launch the program. There’s also a “virtual” GUI remote control for your desktop that launches at the same time.
The first order of business is to do channel scans. You specify whether the signal source is off-air (NTSC, ATSC), or through cable (NTSC, QAM). You can even scan both modes, although you’ll need to change the antenna to a cable connection at some point.
Once the scan starts, the OnAir HDTV-GT will scan and save any active NTSC channels, plus any ATSC or QAM channels for which it can decode program information and virtual channel data. Terrestrial DTV stations will show up in the list sorted by their virtual channel numbers, not their physical channels. Cable DTV channels will be sorted by their physical channel numbers, however.
Figure 3. A screen grab of the HDTV-GT Channel Manager,
virtual tuner control, and display window.
To watch a channel, you simply click on its call sign or number in the Channel Manager, or tune it in with the virtual remote control. The actual video is sized and overlaid in your laptop’s video card using an alpha channel, so you can’t “grab” the frame as well as your active desktop – all you’ll get is a black screen. You can, however, take a snapshot of any frame of video being displayed using the camera icon on the remote control.
If you’ve got hard drive space to burn, you can also time-shift a program for later viewing. Be careful, as HD MPEG data usually requires 9 GB per hour for time shifting. My laptop had a partitioned hard drive with one side limited to 17 GB, barely enough to store 2 hours of video!
Scheduling software is also included. You can set up the tuner to record or simply watch a given analog or digital program, specify the length of the program, and tell the tuner to stay on that channel when done, shut down, or go into sleep mode.
Figure 4a and 4b. These two screen grabs from the Tigers — A’s ALDS game were captured at 1280x720 resolution from the Fox broadcast.
PERFORMANCE
As mentioned earlier, the OnAir HDTV-GT uses the latest 5th generation 8VSB chipsets, so it is capable of reception in high multipath areas. I’ve been taking it on the road for the past few months, checking out 8VSB reception from hotel rooms in Syracuse, NY and Pittsburgh, PA. I also tested long-haul reception of DTV signals from a summer home on the St. Lawrence River in Ontario.
In these locations, the DTV broadcasts are all on UHF channels. The supplied whip antenna is kinda small to have much gain, so I brought along a Silver Sensor log periodic UHF antenna, which worked great in Syracuse and Pittsburgh. At the first location, my hotel room was on the 2nd floor with a view directly to the south at each of the DTV transmitting antennas.
Figure 5. Here’s my receiving set-up on the fifth floor of a hotel in Syracuse. This window had line-of-sight views to all Syracuse DTV towers.
The Pittsburgh location, although high enough on the 5th floor of a Radisson Hotel, did not have a completely unobstructed path. So, I aimed the antenna towards the wall, using AntennaWeb.org headings and a compass. No matter, I picked up every DTV station on the air in Pittsburgh, including two signals off the side of the Silver Sensor.
In fact, this was during a raging thunderstorm, and at one point, a nearby lighting strike knocked out the house DBS TV system. I simply leaned back and continued to watch the Oakland – Detroit ALDS game in 720p HD from local Fox affiliate WPGH-DT without a hitch, despite a few more close strikes. There are advantages to getting your DTV over the airwaves!
In my lab, I ran the same antenna heading tests performed for the review of Samsung’s new 5th-gen DTB-H260F set-top receiver (elsewhere on this Web site), with the same results. Everything the Samsung receiver could pick up, the OnAir HDTV-GT picked up, too.
Figure 6a and Figure 6b — The waveforms for KYW-DT and
WGTW-DT with the correct heading, and with a heading of 295 degrees.
Figures 6a and 6b show the 8VSB waveforms for KYW-DT (left) and WGTW-DT (right). KYW-DT was receivable with a heading of 295 degrees, and even locked up the tuner with my rooftop antenna aimed towards New York City — over 135 degrees off-axis. While aimed at NYC, the OnAir HDTV-GT also picked up WCAU, WPHL, WTXF, WYBE, WPSG, and WUVP from Philadelphia.
CONCLUSIONS
This is a handy little gadget, no doubt about it. It works really well with my laptop and should do just fine with yours, assuming you meet the minimum system requirements (listed). The MPEG transport stream recorder is a nice touch, but watch your hard drive space! There’s also a D-VHS interface to save recordings, assuming you have the requisite Firewire interface on your computer.
TS READER PRO
AutumnWave also shipped me a beta version of TS Reader Pro. Ts reader is a freeware program, but the Pro version adds quite a few features for real-time analysis of MPEG program streams from terrestrial and cable DTV stations. If you think your local DTV station’s HD picture quality is suffering, TS Reader Pro will let you monitor the actual bit rate as it goes up and down. Numbers don’t lie!
TS Reader Pro lets you look at instantaneous bit rates, statistical multiplexing, check all program numbers and packet IDs (PIDs) for video and audio elements. Got a picture, but no audio? Might be an incorrectly assigned or mapped PID.
I’m still testing TS Reader Pro and will have a more intensive review of it on this site in November of 2006. It’s available in a package with the OnAir HDTV-GT for about $600, which pretty much takes away any financial excuses a DTV station might have for not monitoring their MPEG encoders. (You’d be surprised at what some of them use — a consumer-grade set-top box to verify picture and audio are present!)
