A fully charged one cell Lipo is 4.2V. Most, if not all lipo chargers will automatically stop charging once the battery is fully charged. In the RC world, most have a LVC (low voltage cutoff) and that's usually at 3.2V. Your battery was pretty low and I wouldn't be surprised if a low battery is the reason you lost tracking capability.
Ummm, I've been running all my EggFinders with a 2S lipo and yes, one can get away with it using a 1S but I want a steady voltage supplied to the EF. There's a 3.3V regulator on the board and tracker reliability should be strived for.
If the voltage drops too low, power output tanks and range therefore stinks. With a 100mah, 900Mhz tracker this is vitally important. Jim's contention of an RDF backup tracker on a cert attempt that's going up "a ways" is valid.
So much so that I'm going to do it from now on for large projects that can handle the extra tracker and certainly on an L3 attempt.
Remember, not every position with an EggFinder is decoded while the rocket is in flight. I believe it is due to 1. The 100mW power output and 2. The random antenna orientation that occurs with the rocket under drogue affects the polarization of the
signal the can be overcome with increased power output but is limited to 100mW with the EF. Once the rocket settles down under the main chute, I find the decode rate goes up. Only takes one position to find a rocket.
That's where GPS can help because in the event of a ballistic flight one just needs a single position, preferably before it hits, and the hole will be found. I found that out and only had 2 maybe 3 positions come through with an EF flight and I was probably
a little over 100 yards from the impact point. RDF one is out of luck as a bearing likely won't be had nor held without a visual.
I agree, an RDF tracker in Hyperion's case would likely have saved the day. With the luxury of the visual lock, could have "honed-in" on the bearing and if a mapping GPS was used that could lock a bearing, one would have a GPS reference to follow a line
to the last known bearing. (Hold the mapping GPS parallel to the Yagi beam to lock the bearing if the rocket can't be seen.) Folks said they lost sight of the rocket when it was 3000 feet up. The LOS (loss of signal) of the tracker could have occurred much later and the final bearing (plus a mapping GPS to lock the bearing) would have saved the recovery. There would have been a tremendously good chance one could have proceeded to at least the ground footprint of the tracker and home in to make the pickup. Hopefully the rocket will be found and flown again with two trackers and a 2S lipo on the GPS tracker. Matt read up on lipos and chargers to get a handle on this battery chemistry. Kurt