Good point, I was thinking $125 for the Eggfinder tx ($70) plus the LCD rx ($55), but you are right, you would not need a new receiver in the event of a crash landing.
I crashed in EF in a fiberglass rocket. The one position I received was just above the fincan sticking out of the ground. I think I got a replacement during a black friday special. I’ll tell you, a lot easier to swallow than losing a Beeline GPS. I lost one of those too in ‘07. More like $256.00. Interestingly the BL was forward and the Raven 1 deployment altimeter was behind it with a thick plywood bulkhead. Replaced the onboard mini lipo on the Parrot altimeter and I downloaded a perfectly parabolic ballistic flight. G forces on impact were crazy high and probably inaccurate as they exceeded the G limit. Been meaning to put it in a beater rocket and see if it still would perform. The diagnostics say it’s ok.
I’d expect like anything else 4G and probably down the road 5G trackers will become available. The 2G units are likely so freaking cheap because there is such a large ready stock of them on hand and the sellers know 2G is going away. Hence, they’re unloading them. 4 and 5G (yeah science fiction for now) are probably going to cost moolah when they first come out and it will take time for the initial cost to come down. That is what will make a dedicated rocket tracker more enticing. There is a live mapping option for some of the units too. GPS Rocket Tracker is quirky but workable. Hacked Ham Radio software is doable and I’ve used it on a half a dozen recoveries successfully. I’m still learning.
Some folks just want to find a rocket, period. Nothing else. If that’s all that’s all fine and good. Push launch button, rocket disappears, try to scan around with the eyes to see the main event but if it’s not seen due to being too far away, ok just have the rocket phone home. That is if one doesn’t care what’s happening in between launch and recovery. In the case of a core sample, rocket is not likely going to be able to phone home due to the destroyed tracker so that could be a problem with a totally sight unseen flight.
With live streaming, live mapping one can see on a map where the rocket is in flight and with various map presentations, see the GPS mean sea level altitude too. Once a rocket disappears from sight it’s a waste of time to be staring at altitude because winds aloft can make rockets go in screwy directions. It’s not going to end up where you expect based on the ground windspeed direction. I know that from several Ham APRS tracker flights and NMEA 900Mhz tracker flights. What happens with a live tracked flight is as long as one has a “navigator’s brain” they can transpose on the map a bearing to where the rocket is supposed to be in realtime. In otherwords, one knows where to look to have the prospect of “seeing“ the actual main chute event. I’ve tracked rockets (using mainly Ham radio APRS) and the crowd is staring 180 degrees from where I know where the main event is to occur. Of course I call out loudly where to look and sometimes we see it and sometimes we don’t. When we don’t see it it’s because the rocket is too far away to be seen even under parachute. In that regard, the altitude read out gives the good or bad news. If it’s coming in hot one will know it from the readout. If the main deploys, the descent rate slows strikingly, is easily seen on the readout and a sigh of relief can be had as one knows the rocket is in a safe terminal descent. Even if it cannot be seen!
Also if the rocket is seen on descent, if there is concern it will land on a road or say a lake (heaven forbid!) that is easily discernable on the live map. I’ve called out several times that a fliers rocket landed on the launchsite and not a road. There are advantages to live tracking over 2G trackers.
When I got lazy and didn’t want to set up a tablet computer, I’d break out my trusty Garmin 60CsX and run an interconnect cable to a Kenwood D72A to run with a Beeline GPS tracker. Yeah, I know, takes a Ham Radio license but is not that hard. The Garmin will keep track on a map though it’s not a breadcrumb track like can be had on a tablet app. The D72A can have the screen switched to show the GPS mean see level altitude live.
In this case, I didn’t care in realtime where the rocket was because the Garmin would capture the last known position. What I was interested was whether or not the events occurred as planned. The altitude readout gives that information readily. If I looked at the Garmin screen while the rocket was in flight, I’d sometimes see the rocket moving but there is no bread crumbing so the only thing seen is the last known position. That paradigm as everyone knows works very well for recovery. The APRS system is great for being able to concentrate on the altitude and hence whether or not the apogee and main events occurred nominally. Yes it keeps tabs on the position too so one can make the recovery. I’ve been to launches in the past where there was another flier flying a Beeline GPS/Garmin combo. In that case the flier was more interested in watching the Garmin screen and I’d volunteer to tune to his Beeline GPS frequency and set my D72A to call out the altitude while he concentrated on the rocket track. The teamwork approach actually worked very well. I can go solo and steal glances on the Garmin to get the direction and still monitor the altitude readout satisfactorily.
The EggFinder LCD and others I believe can do the same thing as long as positions are received. There are quirks with 900Mhz but enough positions are received to make it a very viable system. The Ham stuff was the only game in town when I started out.
Now with these very small windows tablets it makes it easier to run full featured Ham Radio APRS software with really cool displays such as bread crumbing tracks and live altitude readouts. Some of this stuff can be hacked for the NMEA trackers too. Hence if one gets a Ham Tech license it will give them more choices though for sport fliers, it’s my opinion that 900Mhz is more than adequate.
Kurt Savegnago
