Rayming TN-206 Bluetooth GPS Receiver (Rayming TN-206 Bluetooth GPS Receiver)
for AXIMUSERS.COM
December 15, 2004
By GORRIC
Background
I had a specific application in mind when I decided to evaluate standalone Bluetooth GPS units. My previous experience with GPS was with an early Garmin handheld. As a sailor involved in racing, these units were useful up to a point. That point was usually reached when both hands were needed (which was most of the time) and the unit had to be stuffed into a pocket. Any subsequent bearing check required a wait for the unit to re-acquire a fix. The need to have the unit up and ready continuously is the reason most sailors have moved to fixed chartplotters with fixed antennas that are very expensive for both the units and the charts. Being a thrifty kind of guy, I wanted a system where the antenna was fixed (no delay on re-acquisition), and the “chartplotter” was portable. The solution was some sort of Bluetooth-enabled PDA and a portable Bluetooth GPS unit. I had no idea what a wealth of applications there were and how incredible this technology is! After considerable evaluation, I finally decided on a Dell Axim X30 high for the PDA, Mapopolis for land travel, Outdoor Navigator for sailing with marine charts, and the GlobalSat 308 Bluetooth GPS unit (with a detachable external antenna permanently installed on my sailboat.) I’ve made note of some of the features of this GPS unit below - Remember that “thrifty” was a major motivator, and that the GlobalSat 308 is last year’s model and has dropped in price.
Construction
It’s a little thicker than the average pager, about 3’’ by 2’’. The 98 gram weight puts it at the lighter end of the scale compared to the competition. The nice thing is that it’s bottom-heavy. Combine this with the non-skid bottom surface and the unit stays put even when thrown on a car’s dashboard or a galley counter-top. The external antenna port is for a MMCX/F jack (important if you order a generic antenna.)
Functionality
The chipset is the SiRF IIe/LowPower (SiRF III is out now, but costly), firmware rev 2.3, uses neat things like SiRF trickle mode, supports WAAS/EGNOS (geodetic altitude corrections no less) and allows selection of SiRF or NMEA(marine serial protocol) output. The Bluetooth implementation is sound. I have used several BT devices simultaneously (headset, modem, GPS) without static or crackle.
Battery
One of the best features! It’s got a 900mAh Lithium Ion battery. The AC charger is a narrow, unique shape that fits tight spaces quite well. The charge time is around two hours, and the charge lasts from 6 to 9 hours depending on how active Bluetooth is.
Range
Bluetooth range varies proportionately with the output power level. Bluetooth was designed partly as a low power cable replacement between serial devices with a suggested range of 30 meters. I was in the clubhouse having a beer at least 60 feet (say 20 meters) away from the dock and the GPS was still paired up with Outdoor Navigator! How long a cable do you want?
GPS Sensitivity
It usually takes well less than a minute on a “cold” fix, just seconds for a “hot” fix, and uses all the satellites it sees. I’ve not used the unit much tramping around in the woods, dodging trees and scaling rocks. I have no idea if it loses its fix a lot while under trees. Other reviews I’ve read rates it in the middle of the pack for sensitivity and fix loss. I have used it on a train, (with the unit on the window ledge and the blind shut) and it worked without a loss; while visiting I was sitting 15 feet across from the window in the living room, turned on the GPS and Mapopolis quickly identified our location on this dirt road in rural Canada with only four houses on it.
Pros
• I like the size and weight. It stays put
• Its default config worked with all software
• It works while charging
• I like the flashing lights (I can see when it pairs up)
Cons
• The on/off switch should be recessed – I’ve had it lose the charge after it got jostled in my briefcase and was turned on
• I’d like it to pair with more than one device, but.. for the price
• I don’t like the flashing lights (while driving at night)
Linear Mode
