Can someone explain to me how the rc transmitter/receiver works?
 

<p style="margin-bottom: 0cm" class="western">Hello, I am not sure if I am asking this in the right place, but I guess people with experience might know what I am after. What I would like to know is what data is passed between the transmitter and receiver and how does this data vary when for example increasing the helicopter speed or moving the helicopter to a different direction. I have built a small prototype made from ArduinoUno and a receiver. When I turn my helicopter remote control on and increase the speed I can see a burst of 1's sent to the reciever. Increasing the speed makes it seem as if the burst increase in frequency. However I cannot understand how the reciever on the helicopter interprets these bursts and how it distinguish between for example an increase speed signal and a turn left/right signal. Can anyone help me out?</p>

RE: Can someone explain to me how the rc transmitter/receiver works?
 

Basically, an angular movement in the sticks of the transmitter ends up as an angular movement of one of the servos of the flying machine.
Both deflections are proportional (there is a feature named exponential which makes that proportion non-linear on purpose).

The steps are input deflection -> variable resistance (potentiometer) -> pulses per second of radio wave -> potentiometer of servo motor -> output deflection

That output deflection is used to deflect control surfaces.

For electrical power, the radio wave controls the amount of electricity (pulses) fed to the motor rather than the deflection of a servo.

Check this link for a better explanation:

http://www.rc-airplane-world.com/rad...trol-gear.html

RE: Can someone explain to me how the rc transmitter/receiver works?
 

It is a function Pulse Width Modulation (AKA Pulse Position Modulation), way too complex to explain here, but a series of pulses of finite width is transmitted to the receiver. The width (time) of the pulse is varied by the stick position. There is a quiet period between strings of pulses, that allow the receiver to "reset", then things start all over again. The receiver takeks the pulse string, decodes the space between pulse one and two as channel one, between pulse two and three as channel two, and so forth.

Best I can do here. I recall having seen a complete description (including pulse trains) somewhere, sometime, but don't remember where.

Les

RE: Can someone explain to me how the rc transmitter/receiver works?
 

Some (Spectrum) TX-RX sets (and others) have an additional quirk. When dual servos for such things as ailerons, elevator flaps, etc are involved, the controlling pulse trains can be modified, so that the dual servos control pulses occur in a way that synchronizes the inputs and outputs close together from a time standpoint. Exactly how this works from a technical standpoint ???

RE: Can someone explain to me how the rc transmitter/receiver works?
 

When I was in the old USAF, we had several terms to describe these complexities. A couple of them were: "Works good, lasts a long time" , "PFM" (pure ******* magic) and "smoke and mirrors" The last two would best describe transmitter/receiver/servo interaction to most of us.:)