Radio Tracking

Locating rockets with the BigRedBee beeline

The Beeline transmitter 0.875" wide and 1.5" long. I odered mine with the SMA attachment and I would recommend it as it allows for easy removal or changing of the antenna. The standard antenna is very light but fragile; if it bends your signal may decrease pretty drastically. Also, in rough landings, the battery may swell, disabling your transmitter (and ruining the battery), so I would recommend making sure it is secure and in a safe location inide the rocket. I do not recommend just taping it (or it inside a holder) to a shock cord, however, many people have had success with that method.

I chose to purchase a Smiley 70cm Stubby Duck antenna for my Beeline, which is only ~3" long as compared to the original 7" antenna. It does add weight but I like the tradeoff. No signal losses were detected in a few (basic) tests. I also upgraded to a 350mAh Li-Po battery (standard is 170mAh) so my battery life is almost double - it runs for a significant amount of time (over 32 hours for me) depending on your settings.

I went with the Arrow II yagi antenna as my directional antenna and I would highly recommend it. It is very eas to use and well worth the money. Many people try to cut costs by making their own, which is fine, but if you do not have the accuracy, prepare to lose your rocket and be out of more money than you tried to save. I got the two-piece 7 element which has outstanding directionality to it. I also modified my antenna to move the grip from the boom to a dowel rod screw perpindicular to the boom between the 5th and 6th elements. This makes it far more balanced and allows for a pistol grip hold on it, making your arm take much less abuse from fatigue in the field.

I use the Arrow 4 Mhz. offset attenuator which works wonders. It costs as much as the antenna but it makes finding your rockets twice as easy, so I say it was fully worth its cost. Simply tune your receiver 4 Mhz off (+/- normal transmitting frequency) and turn on the attenuator. You will pick up the signal the same as before, but now when you adjust the attenuator level, the signal will die and you can more easily find the high point direction that you need to find your rocket.

Once you have all the parts, you'll need a few BNC cables to attach it all together. As far as mounting the transmitter, I would suggest the nosecone. I find it the easiest and usually safest. I wrap mine with bubble wrap and tape/rubber band - I usually dont have to worry with the antenna because the Smiley Stubby Duck is much more robust than the standard wire antenna. You can mount them inside an avionics bay if you wish, but note that it may sometimes interfere with your altimeter if you use long wires (which will act like antennas themselves and put discrepencies in your altitude readings and potentially cause your altimeter to fire its charges at "bad" times). Do note that the transmitter can not transmit its signal through metals or carbon fiber - stick it in a fiberglass or paper/phenolic area of your rocket.

Below I assembled a collection of links that will help you in finding the right tools for the job:

  • BigRedBee - The one and only place to get your BeeLine transmitter
  • Yaesu Transceivers - My preferred brand of receivers; check out the VX-3r
  • Arrow Antennas - Best quality yagi dirrectional antennas on the market!
  • CheapHam - Discount HAM radio products (cheaper prices for Arrow products and miscellaneous accesories)

CONTINUE ON TO USING THE TRANSMITTER