User`s manual

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may be living… check with your local fire marshal if you aren’t sure. If you can’t test in your
backyard, check with your local club to see where you can test; they may have an area set aside
during launches for such testing.
4) Batteries can be heavy, especially 9v “transistor” batteries. For best flight performance, use
the lightest batteries that you can get by with. 3.7v single-cell Li-Po batteries work great for
deployment with low-current igniters like a Quest Q2G2, but you need to charge them properly
and solder 24 gauge tinned pigtails to the battery leads, since most of them are very fine and can
easily break under flight stress. After you solder the pigtails, fold the pigtails over and wrap the
battery with a couple of wraps of electrical tape to strain-relieve the delicate battery leads.
You can also find these batteries with various kinds of connectors pre-mounted, you can obtain
the matching connector for them with a pigtail, and solder it to the board. Be sure to put a switch
in-line with the positive (usually RED) side of the deployment connector!
5) Batteries are a lot cheaper than motors and rockets, so if there is any doubt whatsoever about
the capacity of your ignition battery, replace it. When in doubt, TEST THEM FIRST before you
try to fly them, and replace them if they read under 80% of their rated voltage.
A lot of people replace their deployment battery after EVERY flight regardless of the voltage or
the current draw being used. With a 9v Alkaline battery and a Quest Q2G2 igniter this may be
overkill, but for smaller batteries such as an A23 12v battery it may be a really good idea.
Compared to the cost of the rocket, motor, Eggtimer TRS, and last but not least, your time, a few
dollars per launch to ensure that you get a good deployment is cheap.
Of course, if you’re using a rechargeable LiPo battery, this probably doesn’t matter all that
much… the amount of current that a LiPo will put out is huge compared to the requirements of
most deployment igniters/ematches. Just make sure that you test it before every flight, and keep
it charged up.
6) If you are using a pyro ejection charge, you MUST have an external deployment power
switch to disarm the deployment power until shortly before launch. This is a Tripoli and NAR
safety requirement, and is just good common sense too. You can pair up your Eggtimer TRS
unit with your Eggfinder LCD receiver at your prep table, leaving the deployment power OFF
until you have the rocket on the rod/rail, then turn it on right before you start the flight sequence
from your LCD receiver.
If you are NOT using an Eggfinder LCD receiver to arm the Eggtimer TRS, you should shunt the
Reset terminals to put the Eggtimer TRS in “hold” mode, then release the Reset shunt and turn
on the deployment power on the rod/rail to start the flight sequence. This will keep power to the
GPS module, so you don’t lose your fix. We DO NOT recommend powering down the Eggtimer
TRS power until you’re at the pad, like you would do with other flight computers. The GPS
needs to stay powered to maintain the fix. We’ve seen the results of launching without a fix; the
Lost Patrol may still be looking for that rocket…