User`s manual

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When Nose-Over is detected, the Eggtimer TRS begins using the Descent Samples value for altitude
sampling. This setting is very low, 2 samples/sec. As the rocket descends, when the altitude drops
below the Main deployment altitude the Main channel is triggered, for 2 seconds. At this point your
Main chute should pop out, to thundering applause and a hearty round of high-fives all around.
On the Ground
The Eggtimer TRS detects that your rocket is on the ground when the AGL altitude is below 30 feet
for over 5 seconds. Unless you launched from a hill, it’s unlikely that your landing altitude will be
lower than that by a full 5 seconds times the descent rate, which is typically about 20 feet/sec for a
main chute. That works out to a landing altitude 100’ below your launch altitude, which would be
unusual.
What is more likely is that it won’t be able to figure out that you’ve landed, generally because your
rocket landed on high ground or a tree. If that happens, it will continue to record altitude samples at
the Descent Samples setting, until it runs out of flight memory. When that happens, it will call it a
flight.
Once on the ground, the Eggtimer TRS will send out the apogee through the radio until reset. It also
sends out your GPS coordinates, so if your rocket gets dragged on the by the parachute by the wind
(or picked up and returned to the range…) you’ll be able to get an updated fix if y ou have your
Eggfinder LCD receiver with you. It also acts as a verification that you had a successful flight, but
getting your rocket back in one piece pretty much told you that, didn’t it?
After the Flight
Once you’ve noted the maximum altitude so you can brag about it to your friends, you should TURN
OFF the deployment batteries. It’s OK to leave the Eggtimer TRS on until you get back to the
range. Gather your rocket up and take it back to your work table, get a can/mug/bottle of your
favorite beverage, then you are ready to download the data.