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How to measure battery capacity with Arduino
Battery capacity measurement can be useful in many situations. And it is not hard, only requires enough time to discharge battery completely with know resistance and a way to measure voltage in the circuit. Ohm’s law will to the rest: I = U / R Let’s say, we want to measure standard AA 1.5V alkaline…
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Improve Boscam BOS 600 cooling with thermopad
Boscam BOS 600 is a 5.8GHz 600mW 32 channel video transmitter well suited for long range (> 1km) FPV flights. Its design makes the whole casing a radiator. This is good, since 600mW of RF means a lot of heat. Unfortunately, Boscams BOS 600 design has a serious bug there: so what if whole casing…
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VirtualWire support for Raspberry Pi
FS1000A and XY-MK-5V 433MHz RF modules are very often first choice for cheap and dirty Do It Yourself wireless communication. Pair of those , allowing one way radio communication, const less than 3 dollars or euros. So they are really cheap. Limited range and transmission speed limits their real life usage, but simple assembly and…
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Smartport telemetry for Cleanflight
With their latest transmitters and receivers FrSky changed telemetry protocol. XJT module, Taranis radios, X8R, X4R and X4RSB are using SmartPort telemetry protocol. And that creates few problems. First of all, SmartPort is a serial protocol. That means, flight controller has to have free serial port to connect S.Port device. Second of all, TX and…
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Cleanflight 1.12 released
3 days ago, new version of Cleanflight, STM32F1 and STM32F3 flight controller software has been released. I already wrote few words about it a month ago, but final list of changes and improvements is bigger. Main changes are: Looptime sync to gyro readouts, enabled by default (!), New task scheduler, Air Mode. Finally this awesome…
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What is Betaflight Air Mode?
Better late than never, so here is mine explanation what is AirMode implemented in Cleanflights fork Betaflight and hopefully soon available also in Cleanflight. Before we will go to any details, please read this to understand how PID controller works. If you know, you might skip it. In normal flight mode, No Air Mode, flight…
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Is PPM Analog or Digital?
Since I am a huge fan of answering questions when they are asked, here is my answer to “Is PPM Analog or Digita?“ The easiest way to determine if electrical signal (and PPM in case of RC usage is electrical) is analog or digital is to check how many voltage levels are used. If signal…
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Damaged motor: broken off magnet
One of the things that can happen to brushless motors, specially outrunners, is broken off magnet. Stronger crash, or even extensive vibrations, can cause one one small magnets located in motors bell to tear off. After all, they are only glued to rotating part of motor. Symptoms are: If magnet stays inside motor, it will…
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Programming ATtiny85 and ATtiny45 with Arduino IDE
What is ATtiny ATtiny is a fimily of microcontrollers by Atmel, the same company that provides ATmega series used widely in "real" Arduinos. Comparing to ATmega, ATtinys are much simpler, smaller (usually), with less features. But also cheaper, easier to connect, using less energy, and trust me, in many many cases you do not need…