A company called Callpod, Inc.[1] is offering a handful of genuinely slick and useful accessories for your computer or cellphone. One of these, the Dragon™ bluetooth headset, was recently praised[2] by David Pogue in his New York Times technology column. Of course, bluetooth headsets have been around for a while, but this one is distinguished by being very small, having extremely long battery life, and other features, including the ability to communicate as a walkie-talkie with others of its kind in nearby ears. As far as I can tell it does this over bluetooth, after pairing with its partners, so the link might afford some measure of privacy, unlike traditional walkie-talkies. The Dragon is a class-1 bluetooth device, and therefore can operate several hundred feet away from your cellphone or computer (as a Skype headset, for example). Pogue compliments the product’s unusually good sound and ease of use, but his review is his typical friendly and engaging once-over, without much critical penetration. For example, how does the headset, which operates in the crowded frequency band used by microwave ovens and wifi, deal with RF interference?

One might expect that the device’s range as a walkie-talkie would be equal to its range as a computer headset, as, one presumes, the same bluetooth radio is used for both applications. This range, by the way, is claimed on the product page[3] in one place to be “328+” feet (this is just a conversion of 100 meters) and in another place to be “up to” 328 feet. This isn’t the amusing part, just typical marketing vagueness. (I can not provide specific URLs for every detail I quote from their web page, as they use a mixture of javascript and Flash for navigation, but it’s all easy enough to find.) But elsewhere on the page I learn that “Proprietary two-way communication software allows two dragon [sic] headset users to talk over a 250,000 square foot area.” They are talking about the walkie-talkie mode now. But what are they saying? The distance over which the radio can be used is a length, not an area. Obviously some marketing people realized that areas would provide bigger numbers then lengths and, I guess, look more impressive. They must have got hold of a range number from the engineers and turned it in to an area to make it look bigger to stupid people. But what range did they start with? The 328 foot range gives a circle with an area of 338,000 square feet. A circle of area 250,000 square feet has a radius of only 282 square feet. Their “Proprietary two-way communication software” reduces the normal bluetooth range by 14%!

Looking around the page for enlightenment, I find “In open areas, testing has showed [sic] that effective two-way communication was achieved in excess of 450 feet.” The context (this is in the FAQ tab) shows that they are again discussing walkie-talkie operation. Well, 450 feet means an area of 636,000 square feet. Surely the marketing people are being overly cautious. No, I don't think that’s it. I think that they rounded up to 500 feet and squared it. Don’t you?

The marketing people have missed an opportunity for much bigger numbers. I'm not talking about a paltry 636,000. What might happen if someone explained to them that two people, communicating with the aid of $100 devices inserted in their ears (available in three styles, all out of stock) are not limited to a two-dimensional surface? What if one of them is allowed to climb a hill? We’re talking 524 million cubic feet here! I need to get in to marketing. Clearly, I can do much better than these guys.