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+== Installation
+
+ EasyMotor needs to be rigidly attached in the airframe, and the
+ long axis of the circuit board needs to be aligned with the axis
+ of flight. By default, the round beeper on the board should be
+ "up" towards the nose cone, and the screw terminal strips should
+ be "down" towards the fins and motor nozzle end of the rocket.
+
+ === Power Switch and Battery
+
+ In addition to the circuit board itself, EasyMotor needs
+ a power switch and battery to operate. Unlike most other
+ Altus Metrum products, EasyMotor does not work with
+ single-cell LiPo batteries. That's because commonly
+ available inexpensive pressure sensors need 5V, which is
+ more than a single-cell LiPo provides. Any battery that
+ provides from 6.5 to about 15 volts should work. Good
+ choices are the common 9V alkaline battery, or the very
+ small and light A23 12V alkaline batteries.
+
+ Because he often mounts EasyMotor to the motor's forward
+ bulkhead instead of to the airframe itself, Bdale often
+ uses a length of "shooter wire" from an e-match or used
+ motor igniter as a power switch, routing the wire out of
+ the typical fin can vent hole and using "twist and tape"
+ to power up the board. Whatever works!
+
+ === Pressure Sensor
+
+ The primary motivation for designing EasyMotor was to have
+ a reliable way of recording motor chamber pressure during
+ flight. To that end, EasyMotor supports attachment of a
+ low-cost analog pressure sensor. The board provides 5V
+ to power the sensor, and an input for measuring and
+ logging the output voltage from the sensor.
+
+ The kind of sensor EasyMotor is designed to work with
+ takes 5V in and has a linear analog output that ranges
+ from 0.5V at 0 to 4.5V at the maximum pressure supported
+ by the sensor. Very inexpensive sensors that have a
+ "1/8 NPT" threaded input, a "Buick-style" 3-pin connector,
+ and typically ship with a short cable and mating
+ connector, are readily available on eBay and AliExpress.
+
+ To log in-flight chamber pressure, a typical approach
+ might be to drill a 1/8" sampling hole all the way
+ through the center of the motor's forward closure, then
+ drill and tap partially through the closure with a "1/8
+ NPT" pipe tap. Fill the touch hole with grease, screw in
+ the pressure sensor, and attach the sensor leads to
+ EasyMotor.