So for Christmas this year my wonderful wife bought me a BeeLine GPS to add to my rocket collection. It’s a sweet little unit that is 3″ X 1.25″ and weighs about 2 ounces and will fit into a 38mm diameter tube. According to Greg, the designer, we can just pack it in bubble wrap and shove it into a nose cone to get it to fit. Fortunately it has mounting holes so it can also be mounted on a sled for some more stable mounting.
I also received one connector with four wires coming out of it. This is for the Digital Telemetry inputs and can help drive the unit. However, this unit can be used without it.
The BeeLine GPS is a small unit with the GPS antenna on top of it, and the battery shrink wrapped on the back of it. There is also one additional battery that is mounted to the back of the board. I have not discovered what this battery is used for. I have a feeling that it is for keeping the configuration settings when the main battery is not plugged in.
This is a GPS unit which after it gets a lock will start transmitting and APRS packet on the 70cm Ham Radio band. Since this is a Ham band Big Red Bee will only sell this unit to someone with a Ham radio license. I happen to have a General license (KE5KOG) so it was not an issue for me.
An APRS packet is a standard used by Ham radio operators and means Automatic Packet Reporting System and basically just means that it gets the GPS location from the satellites and then transmits its location to anyone listening on the same frequency. For us, that means we just need a radio listening on that frequency, a unit that can decode the APRS packet, and then either a GPS unit that you can enter that location into, or a computer that will show you a map of where the device is located. After that you just walk to the rocket and pick it up. Hopefully no more wandering around in the fields looking for our rockets.
Here is a photo of the unit with the antenna attached and the battery plugged in. The first time the unit is plugged in it can take up to 20 minutes for it to get a good GPS lock. After that it is much faster, but you can’t really tell unless you have a radio since there is nothing on the unit telling you that it’s operating. I was a bit surprised that there was not even an LED on the board that telling me that the power is applied. You better be sure your battery is charged and ready to go becuase the only way to tell is by having the unit plugged in and connected to your computer.
Since I got the package deal it included the combo unit USB interface and battery charger. If you get the BeeLine GPS you really need this part of the deal. It’s the only way you can talk to the unit for the settings, and it’s also a charger for the battery.
It took a bit of reading and talking to Greg on the phone to figure out how to use the unit. Here on the right you will see how the USB charger is used. You plug the battery into it and then connect the USB cable to it.
Then a small LED will light up telling you that the battery is being charged.
To get it to work you first bring up the software on the computer, plug in the USB cable into the computer and interface, then plug in the battery to the unit. Then within 5 or 6 seconds, plug the interface into the connector and then click on read in the program. This keeps the unit and software communicating for the rest of the time. If you miss this 5 or 6 second window then you have to power down the unit and try it again.
(Tip: the LED on the interface will blink on for a fraction of a second and then off when connecting it to the unit. I was kind of worried that it had stopped working, but I learned that this was normal.)
I can’t wait to put this unit into full operation. I have set my next goal in Rocketry to build and fly a rocket to 20,000′. I will be using this unit to track with and additionally have a Rocket Hunter tracker on it. The Rocket Hunter is just a radio transmitter that sends a tone on the 219 frequency.
(You can click on the photos to see a larger version of the images.)