Trendnet ClearSky Bluetooth VoIP Phone Kit

This wireless hard phone for Skype users is affordable, installs easily, and produces decent sound quality.

By Gerry Blackwell | Posted Aug 18, 2006
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On the face of it, coupling Skype, the free Internet soft phone service, with Bluetooth, a short-range wireless networking technology, seems a recipe for flakiness. But Trendnet, a Torrance, California network equipment maker, has produced a portable Bluetooth Skype phone that actually works remarkably well—not perfectly, but well enough.

The Trendnet ClearSky Bluetooth VoIP Phone kit (TVP-SP1BK) includes a feather-light, candy-bar size portable phone (5.6 x 1.78 x 0.9 in., 3.5 oz.) and a USB Bluetooth adapter that plugs into your laptop or desktop PC. The kit was selling online recently for between $67.14 and $110.

If you like to pace while you talk to Skype contacts, or even wander around the office, the ClearSky kit is worth considering. You could also use it at Wi-Fi hotspots or in a hotel room with a laptop. Trendnet claims it will work up to 100 meters (about 300 feet) away from the computer you’re using—but that’s only if both are outside and you have clear line of sight. The range is less if you’re using it inside and going through walls and other obstacles.

The phone, which easily fits in a shirt pocket, features a small (96 x 64 pixel), monochrome LCD for displaying Skype contacts, call status and configuration menus. It also has a conventional telephone number pad, cellphone-style start and end call buttons, a two-way rocker switch for scrolling menus and lists, and three dedicated navigation buttons. And there is a rocker switch on the side for adjusting volume, and a headset jack.

Wideband or narrow?
Trendnet doesn’t indicate whether the ClearSky phone uses wideband audio. Skype uses more bandwidth to transmit voice than the public switched telephone network (PSTN)—it’s wideband rather than narrowband. On good Skype connections with a wideband-capable headset, sound quality is better than on the PSTN—voices sound fuller and more lifelike. Based on my testing, I’m assuming this phone is not wideband capable.

The phone charges through a provided USB cable—you can plug it in to any powered-on computer and start charging even before installing the Bluetooth system. Trendnet claims the slender, lightweight lithium-ion battery provides 60 or more hours of standby time and at least six hours of talk time, which should be plenty for most people. The company does recommend you charge it for at least six hours the first time to ensure optimum battery life, though.

The simple menu system on the phone lets you view call history, set your Skype presence status, pair the phone with the Bluetooth system on your computer (see below), display SkypeOut credits and choose a ring tone from the four not very exciting options provided.

To set up the phone, you first need to have Skype installed on the Internet-connected PC you’re going to use. Then you install the Trendnet software on the PC. It includes a Toshiba Bluetooth stack, a Bluetooth utility for finding and pairing with the phone, and the phone driver that links it to your Skype software and lets you synchronize contact lists and interact with Skype from the phone.

The included Quick Installation Guide that describes this process is slightly flawed in that the illustrations of the screens you’ll encounter are so small you can’t make out what they say and the English in the instructions is sometimes flawed. On the other hand, the process is so automatic, it really doesn’t matter. Based on past experience with Bluetooth, I was expecting a more complicated process, but the job of pairing my PC with the ClearSky phone was done almost before I realized it.

One warning
While the Toshiba Bluetooth stack will co-exist with the Microsoft Bluetooth system used with some of Microsoft’s wireless keyboards and mice, don’t attempt to pair the Microsoft hardware with the Toshiba Bluetooth stack. I did, thinking I could dispense with the Microsoft Bluetooth adapter, and in the process temporarily disabled my mouse and keyboard. I had to manually power the computer down, connect wired mouse and keyboard, power up again and go through the process of setting up the wireless mouse and keyboard all over again.

Using the phone is simple enough. The Home screen displays your Skype contacts three at a time, with status icons. Scroll down to the one you want. With the contact highlighted on the phone’s screen, press the green Start button. You’ll hear the usual Skype sound effects indicating a call is being placed, and the Skype software pops up on your PC screen. Then if the call goes through, you’ll hear the phone at the other end ringing.

To dial a regular telephone number using SkypeOut, you need to press the 0 key, which is also the + key, first. If you forget this procedure and try to press a number key—the 1 or the first digit of the area code, for example—nothing happens. This is perplexing until you catch on, but it prevents you dialing the entire number and then having the software tell you you’ve dialed an illegal number, which is what happens if you’re using the PC Skype software.

Testing any Skype device can never be entirely conclusive. There are so many variables—conditions on the Skype peer-to-peer network, the firewall settings on a corporate network if you’re calling someone in an office, the quality of the headset the other person is using—and of course the device itself.

How we tested
I tested the ClearSky phone by calling Skype contacts and then wandering around my property—I work out of a home office—to test the range. Incoming audio quality was quite good even when I was outside and the signal was passing through two or more walls It only began to break up when I was over 100 feet from the Bluetooth adapter. There was often low-volume background noise, but it was like white noise, and barely noticeable. Voices from the other end were consistently clear—though decidedly narrowband.

The audio coming from the ClearSky phone wasn’t as good, however. In some cases, there was clicking and popping in the background that could be quite obtrusive and audio sounded slightly tinny, though the voice remained intelligible even when the phone was over 50 feet away from the computer with walls in between. In other cases, the voice sounded wavery and began to break up when the tester was more than 50 feet from the computer.

There were more problems on calls to Skype contacts in offices, possibly due to firewall issues. The people I called more than once reported the signal beginning to break up when I was 40 feet or less away from the Bluetooth antenna. Incoming audio was also slightly degraded, but still superior, apparently, to outgoing.

I’m not sure to what extent any of these symptoms can be unequivocally attributed to the ClearSky phone. On some SkypeOut calls, incoming audio broke up so badly that the connection was no longer viable. But my experience is that SkypeOut calls often don’t work as well as Skype-to-Skype calls anyway, possibly because of latency introduced when going through the VoIP-PSTN gateway.

Bottom line
The ClearSky phone worked well enough most of the time to carry on a normal conversation. At $65, which it soon will be if it isn’t already, it’s a good deal.

There is at least one better-performing alternative if all you want is wireless Skype for the home or office. GN Netcom’s GN 9350 dual-mode VoIP-PSTN headset sounds better than the ClearSky phone, especially at maximum range. But it also costs $300, and you can’t easily take it traveling because it’s fragile and the base station is bulky. With the ClearSky kit, you get a shirt pocket-size phone and a Bluetooth adapter not much bigger than a thumb drive. Bon voyage.

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