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== EasyMini
.EasyMini Board
image::easymini-top.jpg[width=400]
EasyMini is built on a 0.8 inch by 1½ inch circuit board. It's
designed to fit in a 24mm coupler tube.
You usually don't need to configure EasyMini at all; it's set
up to do dual-deployment with an event at apogee to separate
the airframe and deploy a drogue and another event at 250m
(820ft) to deploy the main. Install EasyMini in your airframe,
hook up a battery, igniters and a power switch and you're
ready to fly.
=== EasyMini Screw Terminals
EasyMini has two sets of four screw terminals near one end of the
board. Using the picture
above, the top four have connections for the main pyro
circuit and an external battery and the bottom four have
connections for the apogee pyro circuit and the power
switch. Counting from the left, the connections are as follows:
.EasyMini Screw Terminals
[options="header",grid="all",cols="2,3,10"]
|====
|Terminal #|Terminal Name|Description
|Top 1
|Main -
|Main pyro channel connection to pyro circuit
|Top 2
|Main +++
|Main pyro channel common connection to battery +++
|Top 3
|Battery +++
|Positive external battery terminal
|Top 4
|Battery -
|Negative external battery terminal
|Bottom 1
|Apogee -
|Apogee pyro channel connection to pyro circuit
|Bottom 2
|Apogee +++
|Apogee pyro channel common connection to battery +++
|Bottom 3
|Switch Output
|Switch connection to flight computer
|Bottom 4
|Switch Input
|Switch connection to positive battery terminal
|====
=== Connecting A Battery To EasyMini
There are two possible battery connections on
EasyMini. You can use either method; both feed
through the power switch terminals.
One battery connection is the standard Altus Metrum
white JST plug. This mates with single-cell Lithium
Polymer batteries sold by Altus Metrum.
The other is a pair of screw terminals marked 'Battery
+' and 'Battery -'. Connect a battery from 4 to 12
volts to these terminals, being careful to match polarity.
=== Charging Lithium Batteries
Because EasyMini allows for batteries other than the
standard Altus Metrum Lithium Polymer cells, it cannot
incorporate a battery charger circuit. Therefore, when
using a Litium Polymer cell, you'll need an external
charger. These are available from Altus Metrum, or
from Spark Fun.
=== Using a Separate Pyro Battery with EasyMini
As described above, using an external pyro battery involves
connecting the negative battery terminal to the flight
computer ground, connecting the positive battery terminal to
one of the igniter leads and connecting the other igniter
lead to the per-channel pyro circuit connection.
To connect the negative pyro battery terminal to EasyMini
ground, connect it to the negative external battery
connection, top terminal 4.
Connecting the switched positive battery terminal to the pyro
charges must be done separate from EasyMini, by soldering
them together or using some other connector. Note that for
safety, you must put a switch between the pyro battery and
the rest of the circuit!
The other lead from each pyro charge is then inserted into
the appropriate per-pyro channel screw terminal (top
terminal 1 for the Main charge, bottom terminal 1 for the
Apogee charge).
=== Using an Active Switch with EasyMini
As explained above, an external active switch requires three
connections, one to the positive battery terminal, one to
the flight computer positive input and one to ground. Use
the negative external battery connection, top terminal 4 for
ground.
The positive battery terminal is available on bottom
terminal 4, the positive flight computer input is on the
bottom terminal 3.
|