Category: Electronics
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Read RC PWM signal with Arduino
Arduinos are cheap and simple development board. You can do a lot with even the simplest of them. For example build you own quadcopter and flight controller (after all MultiWii = Arduino + MPU6050). Of course, this is not as simple as one might imagine and there are few (actually a lot) obstacles that needs…
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Note on Arduino Uno servo jitter
Yesterday I discovered very nasty feature of Arduino Uno (and all other AVR ATMega328 boards) when using servos. Although official Servo library states that it can support up to 12 servos on Arduino Uno (more on advanced boards as Mega), it does not say much about quality of PWM signal. Since all connected servos (in…
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Using transistors as switches
I think all popular computerized DIY devices like Arduino, Raspberry Pi or any other microprocessor/microcontroller based boards has one common drawback: low output current. Few miliamps per pin. While this is enough to light a single LED or provide input to other electronics device, it is far from enough to run a motor or power…
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DIY FPV LC power noise filter
Both electrical motor and ESC are source of electrical noise that influences all devices connected to the same battery. This is why, very often, on airplanes or big multirotors FPV circuit is powered from separate battery. On small or medium drones this can be hard to archive: additional weight will influence both flight performance and flight time.…
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Raspberry Pi: reset external I2C devices (not only I2C)
Electronic, and specially computerized, devices likes to hang from time to time. There are many reasons: software bug, hardware error, voltage drop, interference, too long wire, random incident. I’ve learned this hard way during work on my Raspberry Pi based weather station. From time to time external DTH22 temperature/humidity sensor refused to work. Only solution…
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Raspberry Pi + MOSFET = High power switch
With all the possibilities, Raspberry Pi requires additional hardware to turn on and off any additional hardware. GPIOs built in power limit is low: 3.3V, 16mA per GPIO, but not more that 50mA total). And while it might be enough to light a small LED, it is not enough for anything else. Forget about motors,…