Use of Trackers

I no longer maintain a tracker list because the introduction of GDPR would require me to have explicit agreement from everybody appearing on it. Getting this would have been almost impossible because the only details I held were the flier's name, the frequencies of their bugs and the type of equipment they used. In any case, the list was getting increasingly inaccurate because:

• I didn't keep addresses or contact details
• Many of the names and frequencies were provided by tracker suppliers and had no contact details
• Fliers mostly don't let me know when they become inactive.
• I seldom heard who the new owner was when equipment changed hands.

Tracking system usage

I hope the following notes are useful if you're a new user of trackers for free flight models.

• Try to avoid having bugs on the same frequencies as people you normally fly with. Combining that with the frequencies your tracker supplier has used already will give you a good idea of the frequencies to avoid.
• Make sure your bugs are on different frequencies so that:
  • switching bugs lets you avoid clashes with other people's bugs
  • you won't clash with yourself if you leave a model out and fly another before you've retreived the first one
• When you get the trackers, be sure to check the ground range against your receiver with its standard rubber duck antenna fitted. You should get around 1 km with the model on the ground and 25+ km in the air. If you get noticeably less ground range, check your receiver against a friend's one and replace yours if its noticeably worse.
• I've not tried using scanners, but I have a feeling that some are less sensitive than fixed frequency receivers and they may not cover the frequencies we use. I bought a Uniden UBC75XLT scanner to cover airband (108-137 MHz). It covers a lot of other frequencies too, but not the UK animal tracking band we normally use (173-174 MHz).
• A fixed frequency receiver may be more convenient once you've put your tracker frequencies into it. Check eBay for bargains and for used transceivers. The latter may be restricted to transmitting on restricted channels, e.g. 2M (142-144 MHz) while still being able to receive anything from to long wave (200 kHz) to 999 MHz.
• Buying or building a Yagi antenna will raise the range quite a bit and is an alternative to using the rubber duck antenna and body shielding to get direction, but is a bulky thing to lug round. BTW, the null point with the Rx against your chest and the model behind you gives a far more accurate direction than trying to work with the loudest signal in front of you and is an essential skill whenever the model is in crop, etc. IOW when you can't see your model on the ground before setting off after it.
• I also bought a magnetic base HAM radio 1/4 wave whip antenna. It doesn't get much use but makes life easier if the model goes far enough to need a car for the retrieve. Put the antenna on the roof, run a coax lead through a window to the receiver and follow the line with a satnav or GPS while listening for the tracker.
• Long retrieves, especially if the model is over a hill or has landed behind trees or buildings, can be a lot easier if you have a hill-walker's GPS (or an old Garmin GPS II+, eTrex or Geko - all available on eBay as of late 2018). To use the GPS:
  • stand where you watched it down from and make a waypoint on the GPS at that point
  • use binoculars and compass to put a remote waypoint on track well past where you think the model landed, using the bearing and an overestimate of distance flown. If you have an anemometer, read the windspeed, double it and use that plus the flight time to estimate the distance.
  • Add a route from the local to the remote waypoint.
  • follow the line until you hear the tracker. Doing it this way makes sure you can stay on line, even after detouring round hedges, farm buildings etc.
• Beware that wire fences can reflect the tracker signal and give an erroneous direction to the model: been there, done that. Noticing that the signal bearing changes unexpectedly is your clue that this is happening. I discovered that when a long flight from Salisbury Plain (TA10) ended up 0.6km past the A303. Very strong reflections from a wire fence on a hill off to one side of the track misled me into going up the hill that evening and not finding the model before dark. The next morning I found the model quite easily, having walked past it the previous day when following the reflected signal.