Eggtimer Rocketry Eggtimer User Manual page 29

Take the rocket off the rod/rail, remove the igniter from the motor, open up the payload bay,
disconnect all batteries, and fix the failed condition. Then, you can start all over having
hopefully learned one more thing to check in the future...
You can see that if you're doing multiple deployments, it's a lot more involved than just stuffing
some wadding and the parachute into the tube, popping in the motor, and hooking up the igniter.
Multiple deployments require discipline in order to make them work reliably; we've seen way more
than our share of failed deployments, on everything from a small mid-power E-size rocket all the
way up to an M-sized 200 pound beast. We've seen deployments fail with the top-end flight
computers and with the low-cost units, even with redundancy. The reality is that most deployment
failures are not the fault of the electronics; it's usually something mechanical like a bad connection,
a nose cone that's too tight, etc. Having your blood, sweat, and tears free-fall from a few thousand
feet and bury itself in six feet of dirt is going to ruin your whole day.
We STRONGLY recommend that you use a checklist every flight so that you don't forget anything.
We have some on our website under the Downloads section (at
www.eggtimerrocketry.com/downloads
NEED to use one. There are also plenty of other resources online, Google is great for finding them.
We also recommend that you get a copy of the book Modern High Power Rocketry , it's full of good
information too, and subscribing to a forum like The Rocket Forum (www.rocketryforum.com) is a
really good idea, too.
The Eggtimer Flight Sequence
At the Pad...
As you know by now, when you first turn on the Eggtimer you get a long "I'm running" beep
followed by 30 seconds of short beep-beeps to indicate that you're in programming mode. When
you're at the pad and the programming beeps stop, that's when the fun begins...
At that point, the Eggtimer looks at your flight profile to determine what deployment channels to
test, whether it needs to test the breakwire, and it does some internal tests as well. If everything is
OK, it goes on to the "Ready for Flight" sequence, indicated by a 10 second long beep. When the
Ready for Flight beep stops, you will hear continuous chirping that indicates that altitude samples
are being taken and saved to the pre-LDA memory, so the rocket may be launched at any time. If
the Telemetry feature was enabled, elapsed time and altitude data will start streaming to the data
port, and if you have an RF link you will see that data on your monitor.
If the Eggtimer fails a self-test, you will hear a high-low beep tone that counts out the error code
instead of the "Ready for Flight" tone. This means that the Eggtimer has aborted the flight sequence
due to a hardware problem, AND YOU SHOULD NOT LAUNCH. Deactivate the Eggtimer,
disconnect the batteries, disconnect the motor's igniter, and correct the error before attempting the
flight again.
) or you can create your own... the main thing is that you
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