Acronyms Stands For Explanation
ACC Accelerometer A device that measures acceleration forces in a specific direction.
Active Braking AKA Damping Light. A feature in BLHeli that improve throttle responsiveness.
AH Altitude hold A flight mode that maintain height, it uses “BARO” sensor
AIL Ailerons Also known as roll
AL Auto Levelling A flight mode that allows the copter to stay level. It uses “ACC” sensor
ALT Altitude The vertical distance you are from ground
APM Ardu Pilot Mega A type of flight controller board
Arducopter A flight controller firmware software
ARTF Almost Ready to Fly An ARTF aircraft package usually includes everything you need to fly, but it requires simple assembly.
AUW All up weight Max weight of a copter including LiPo Battery and other parts, ready to fly
BARO Barometric Altimeter It measures altitude by using barometric pressure
BEC Battery Eliminator Circuit A voltage regulator found in some ESCs. Designed to provide constant 5V voltage for RC equipment such as Flight controller and radio receiver
BNF Bind and Fly A BNF plane, helicopter, or quadcopter requires only one thing to fly: a BNF transmitter with enough channels. If you’ve got such a transmitter you are all set! Otherwise you just need to buy one.
Bootloader Special code stored in non-volatile memory in a microprocessor that can interface with a PC to download a user’s program.
CC3D CopterControl 3D A type of flight controller
COG or CG Center of Gravity The average location of the weight of a copter. It’s important to make sure the COG of your copter is right in the middle (or close enough)
Crius A type of flight controller board
DD Direct Drive A type of prop designed to go straight on a motor shaft without a gear reduction.
DOF Degree of Freedom It give clues as to whats on the “IMU”. For example 6DOF = 3 axis Gyroscope (gyro) + 3 axis acc; 9DOF = 3 axis Gyroscope + 3 axis Accelerometer + 3 axis Magnetometer; 10DOF = same as 9DOF and adds a Barometric Altimeter
Drone An unmanned aircraft that is guided remotely by a pilot. For military use, these aircraft have weapons and/or surveillance gear. For personal/recreational use, these aircraft often have HD cameras. The term is popular in the media and can be misleading sometimes.
DSM / DSM2 / DSMX These are proprietary technology of an RC equipment maker, Spectrum, and DSM stands for “Digital Spectrum Modulation”.
DSSS Direct-Sequence Spread Spectrum DSM uses Direct-Sequence Spread Spectrum (DSSS) modulation technique. As with other spread spectrum technologies, the transmitted signal takes up more bandwidth than the information signal that modulates the carrier or broadcast frequency. The name ‘spread spectrum’ comes from the fact that the carrier signals occur over the full bandwidth (spectrum) of a device’s transmitting frequency.
EEPROM Electonically Erasable Programmable Read Only Memory A type of non-volatile memory used in computers and other electronic devices to store small amounts of data that must be saved when power is removed, e.g.,static calibration/reference tables. Unlike bytes in most other kinds of non-volatile memory, individual bytes in a traditional EEPROM can be independently read, erased, and re-written.
ELEV Elevator Also known as pitch
EMI Electromagnetic  Interference EMI is disturbance that affects an electrical circuit due to either electromagnetic induction or electromagnetic radiation emitted from an external source.
ESC Electronic Speed Control The ESC is used to convert signal from Flight controller or radio receiver, and apply the right current to the  electric motors. It also usually includes a Battery Elimination Circuit (BEC), which provides power for the RC system and other onboard electronics.
FAA Federal Aviation Administration An United States Department of Transportation Agency, it has authority to regulate and oversee all aspects of American civil aviation.
FC Flight Controller Flight Controller is the brain of your multirotor.
FET Field-effect transistor FET is a device which enables us to use one smaller electrical signal to control another bigger one.
FOV Field of View A measurement how much environment you can see through a camera lens. Usually measured in degrees.
FPV First Person View A technique that uses an onboard FPV camera and wireless connection, to allow a pilot on the ground to see a live stream video while flying, throught a FPV goggle or monitor.
FTDI Future Technology Devices International The name of the company that makes the chips. A standard to convert USB to serial communications. Available as a chip for boards that have a USB connector, or in a cable to connected to breakout pins.
GCS Ground Control Station Software used to monitor a Flight Controller Board. The OpenPilot GCS for example.
Gimbal A specialized camera mount which have the ability to rotate and tilt using servos or brushless motors. This allows the camera to stay in the same position, regardless of the drone’s movement, making for a very still and smooth looking image.
GIT A version control system for software developers.
GPS Global Positioning System Used to track movement or hold position at pre-defined coordinates
GND Ground Ground of a electrical circuit
Ground Effect
GYRO Gyroscope Provides the angular velocity around 3 axes of space in degrees. Assists with keeping a quadcopter level and facing the same direction.
HEXA Hexacopter A type of multicopter, that has 6 motors, no servos, all motors on same level.
HK Hobbyking A famous RC Vendor based in China but with EU, US, AU, RU warehouses as well.
I2C Inter-Integrated Circuit A serial bus that allows multiple low speed peripherals, such as sensors, to be connected to a microprocessor.
IMU Inertial Measurement Unit A Break Out Board containing sensors that reads and sends data to the flight controller
JST-SH A type of Connector
Kalman Filter The algorithm used in Multicopter Flight controllers. It is primarily used to combine accelerometer and gyro data to provide an accurate description of aircraft attitude and movement in real time.
KK Kaptein Kuk Multicopter controller by Rolf Bakke
LC FILTER An LC Filer is a circuit that removes frequencies (noises) from a power supply and smooths / cleans it so the equipment being powered
LIPO Lithium Polymer Battery Aka LiPoly. Most used power source for RC Hobby these days because of its high energy storage density-to-weight.
LOS Line of Sight When you are flying your aircraft by watching your aircraft directly, you are flying LOS. The way of flying is FPV.
LPF Low-pass Filter A technique that filters out high frequency signal
MAG Magnetometer An electronic compass – used to let our FC ( Flight Controller ) know which direction it is pointed in, compared to the Earth’s Magnetic field
MegaPirate a flight controller program software that copies Arducopter
MWC MultiWii Copter MultiWii is a general purpose software to control a multirotor RC model. It can use various sensors but was initially developed to support Nintendo Wii console gyroscopes and accelerometers
OCTO Octocopter A type of multicopter, that has 8 motors, no servos, all motors on same level.
Oneshot Oneshot125 A faster way of communication between FC and ESC.
OSD On Screen Display A piece of hardware that overlays flight data in text or graphical form over an existing live stream video.
PCB or PWB Printed Circuit Board A board with copper traces used to connect various electronic components such as ESCs, Video transmitter LEDs etc.
PID Proportional Integral Derivative The three parameters that you can adjust to change the copter’s flight performance. In theory PID is a control loop that attempts to minimize the difference between a measured process value and its desired value by adjusting the control input of a process.
PPM SUM (CPPM) Pulse Position Modulation A way of sending sequence of multiple signals down one signal wire
PWM Pulse Width Modulation The square-wave signals used in RC control to drive servos and speed controllers.
QUAD Quadcopter A type of multicopter that has 4 motors, no servos, all motors on same level.
RC Radio Control The foundation of our hobby, it’s also used to refer to the hobby as a whole, radio controlled cars, multirotor, planes boats and more.
RCG RCGroups A very popular RC forum
Revo Revolution The 3rd generation of OpenPilot Controllers
RF Radio Frequency Common frequency bands RC hobby use are 5.8gHz, 2.4gHz, 1.2gHz, 433mHz, 900mHz Not all bands are available in all countries, and some require a HAM (Amateur Radio Operator) license.
RPM Revolutions Per Minute the number of times a motor shaft  rotates a full cycle in 60 seconds
RSSI Received Signal Strength Indication RSSI is a measurement of how good your radio signal is.
RTF Ready to Fly Refers to the multicopter you buy has everything you need to start flying. You just open up the packaging, charge and install the batteries, and off you go!
RTH Return to Home A GPS feature that when enabled, it returns the aircraft to the “home” position where it took off.
RTL Return To Launch Same as RTH.
RUD Rudder Also known as yaw
RX Radio Receiver A device that receives commands from our radio Transmitter, and sends them directly to the servos or to the Flight Controller.
SBUS SBUS is a type of serial communication protocols, shared by Futaba and FrSky, that supports up to 18 channels using only one signal cable. Check out this post about different radio signal
SF Slow fly Propellers that are designed to go on a motor using a gear reduction to lower prop speed
SimonK A famous ESC firmware optomised for multirotors
SMA and RP-SMA Sub-Miniature Version A – Reverse Polarity SMA Different Connectors for FPV gear.
Throttle Controls on your radio transmitter, it changes the speed of the motors
TRI Tricopter A type of multicopter that has 3 motors,  one servo for yaw, all motors on same level
TVL TV Line TVL (TV Lines) is basically a measure of how good the FPV camera resolution is. The number is based on how many alternating black and white lines can be displayed in its image horizontally.
TX Transmitter A device that sends our commands to the Receiver, controlled by the pilot.
UART Universal Asynchronous Receiver/Transmitter Serial communication port. A piece of computer hardware that translates data between parallel and serial form.
UAV Unmanned Aerial Vehicle Aircraft without a human pilot onboard. Control is provided by an onboard computer, remote control or combination of both.
UBEC Universal Battery Elimination Circuit a DC voltage regulator
Vcc Vcc Positive power supply input
VRX Video Receiver A device that receives video signal from our video Transmitter, and display the live footage on our FPV goggle or screen.
V-tail A type of multicopter that has 4 motors, 2 tail motors form a V shape, has no servo
VTX Video Transmitter A device that sends video signal to  our video receiver, video captured from a on-board camera.
X8 A type of multicopter that has 8 motors and of a shape of X,  4 motors on top, 4 motors at bottom, no servo
XT60 A type of connector
Y4 A type of multicopter that has 4 motors, 2 tail motors one on top of ther other, it looks like a tricopter but has no servo
Y6 A type of multicopter that has 6 motors and of a shape of Y,  3 motors on top, 3 motors at bottom, no servo
Yaw Flight term used to describe the rotation of a drone around it’s center axis. Controls which direction the quadcopter is facing.

Beecore motor wiring — just remember

Positive leads are on the outside of the board.

New 250mm Build Project (Part 3)

Got everything wired up (needed to solder an ESC wire back), added props, configured Failsafe in BetaFlight (needs Expert mode to display the Failsafe tab), configured Failsafe in Taranis (page 2/12).

Added props, then took it inside our outdoor canopy, just in case it decided to fly away.

Slowly powered up… 100% throttle, and it wouldn’t lift off the ground!

Going to the local store to try 6″ props, otherwise I’ve got more fundamental issues to look for.

New 250mm Build Project (cont.)

Using XSR+ receiver and Taranis X7.

Set my BetaFlight Receiver tab like this: (from Not sure which parts are essential there.

This was essential, though… BetaFlight Configuration tab, set Receiver to “Serial-based receiver (SPEKSAT, SBUS…)” and Serial Receiver Provider to “SBUS”:

Bind procedure is to power receiver while holding down button in upper left, then using “[Bnd]” from Page 2 in my model’s configuration on the Taranis. I’m using the “Internal RF”, set to D16 mode. Powering receiver like that will give a flashing red light. Binding will make the change the light; cycling power will give just a steady green light on the receiver.

Changed Channel Map in Betaflight “Receiver” tab to “TAER1234”. This seems to be my default.

Channels 1-3 are rock steady at 1500 with no mod. Nice. Throttle shows 987-2011 by default.

Going to power up everything and see how the transmitter plays with the quad next.


Needed to enable switches on the Taranis so that they would be available in BetaFlight. Thanks to @UAVfutures:

I set up modes like this, though I don’t yet have a beeper installed:

New 250mm Build Project

Frustration with getting the ESCs to work. Built with:

  • 250mm Frame
  • F4 Revo FC
  • Matek PDB
  • Racerstar MS-Series 15A ESCs
  • EMAX XA2212/980KV Motors
  • GemFan 5030 Propellors
  • FrSky XSR+ Receiver

Wired motors with CCW ESCs wires switched; CW were wired straight across.

Fitting the components on this frame was a challenge as well, as the PDB wasn’t designed with the frame cavity in mind. Also, the PDB called for 3-4S, so my 2S batteries were going to sit this out.

Wiring the FC was also troublesome, though all on me. First time installing pins, chose the ESC connections for this method. For ESCs, I only needed Ground and Signal, so I cut up pins for the top and bottom rows of vias. The spacing for the female connectors to the pins was too tight to fit the connectors adequately, so that took some adjusting.

I avoided a potentially huge mistake. I got turned around on the schematics when wiring up power to the FC, and mistakenly wired two positive vias on the FC to the 5V feed from the PDB. ESCs wouldn’t start up properly, USB said the device was drawing too much power, even measuring the PDB feeds to the FC would come up with just millivolts. Finally, I corrected that, and was then able to make headway on my ESCs.

Trouble with the ESCs… random attempts at getting proper protocol selected, finally got it to MULTISHOT, and then calibrated in BetaFlight.

Initially, this FC was flashed with RaceFlight, but with all the trouble I was having, I flashed down to BetaFlight. I think I can still go back to RaceFlight since all the problems were of my own making.

Big lessons on motor mounts needing to match frames, btw. I had ordered some Kensun 1806 2300KV motors, but while the prop shaft was the correct size for my 5″ props, the closer pair of screw holes in the motor were too narrow for my frame; this was after ordering this size motor based on suggested from the frame’s product page.

I’m punting here, using my old EMAXs, my first El Cheapo brushless purchases, along with the ESCs which were Christmas 2016 specials, no longer even listed on Banggood. In order to use the EMAXs, though, I drilled out my 5″ props to fit the larger prop shafts… we’ll see if this was a good idea, I worry about the balancing of the props.

Overall, good practice soldering. I was surprised over and over at how resistant to re-melting my solder joints were. Even with flux, tightening my solder iron… 370° C didn’t seem hot enough. I didn’t change the temp, though, just worked through things slowly, getting more of a feel for working with solder in its various states.

I attached the FrSky XSR+ receiver that was installed on the used Atom V2 that I bought. This will be the first attempt at binding with a Taranis, the first time I’m using a protocol other than DSM2/DSMX. The Rx is wired, and powers up. This is my next step.

Here’s a pic with props dry fit:

Setup Taranis X7

Models for Deviation

Brand Model Type Module Protocol Date Comments
Eachine E010 Quad NRF24L01 MJXq 2016/08/30 Select “E010” format option
JJR/C 1000 Quad NRF24L01 V202 2014/05/11 1000A and 1000B
Eachine H8 mini Quad NRF24L01 Bayang 2016/04/13
Hubsan X4 (H107) Quad A7105 Hubsan4 2014/02/19
Cheerson CX-10A Quad NRF24L01 CX10 2016/05/14 Select “Blue-A” format option

What is a FET?

Configuring Atom V3, don’t forget…

to set “align_board_yaw”!