Beginners Guide Part 1 - Radio

Enter into the Hobby!

Before we begin, you must decide how much you are interested in modeling. This hobby asks a lot of free time, but also money. I say this in order to immediately be able to skip the toys from  a variety of different Chinese stores.

Choosing the Radio (transmitter)

Let us start from the transmitter as a crucial element.
As a minimum you need transmitter with 4 channels (throttle, aileron, elevator and rudder ).
Every RC modeler will recommend that you don't save money on transmitter. Once purchased, the transmitter will rarely be changed, so I recommend a minimum of a six channel transmitter with which you still have room for improvement. The transmitter will be used for all of your models.
All newer transmitters use 2.4 GHz spectrum (instead of 35/40/72 MHz) as well as Wi-Fi networks, and do not need be paired with crystal quartz to use a specific channel. Transmitters at 2.4 GHz themselves paired with receivers, are more resistant to interference and there can not happen for two modelers to use the same frequency and interfere with each other.

Minimum specifications for transmitter:

- operates on a frequency of 2.4 GHz
- min. 6 channels with all standard mixers
- the ability to memorize at least ten models
- availability of various types of receivers
- quality radio link protocol (DSMX, FAAST, FAASTEST, hott ...)

Speaking of 6 channels, there is little chance that you will initially fly model that will need all six channels, but it's not impossible.
But in almost every model you will use mixes. Mixes combine the movement of two or more servos into a single command. These are the most common mixes, with many transmitters already have pre-configured for ease of use:
- mixer for ailerons (if each aileron has its own servo)
- elevon mixer (models with delta wings, flying wings, and other miscellaneous tailless airplanes)
- the V-tail mix (usually seen in gliders)

Among other functions that every transmitter should have, the most important are: reverse, dual rate and expo. These functions are related to each channel, it means that they do not mix several channels.

Reverse means that you want your servo to change the direction of rotation relative to the transmitter stick. (This allows you to, among other things, don't  care how you position the servo when installing it in the model).
Dual Rate (D/R) is particularly important with high speed and 'nervous' models, where you want to reduce the maximum deflection of the control surface (aileron, elevator, rudder) relative to movement of the stick. Eg. Dual Rate of 50% means that if you move the stick to the end, servo will turn only half as much as it usually can.

Expo is very similar to the Dual Rates but the ratio of moving sticks and servos is not linear, instead it is in the form of a parabola. How can that be useful ? Well, you want to eg. soften servo arm movement with a gentle stick motion, but you still want that the servo horn comes to it's maximum when you move the stick to the end. These 'fast and nervous' models can then be easy to fly with moderate movements of the sticks while the model is flying under a higher speed, and when the engine stops and the model becomes slower and sluggish, you can land using the full swing of the control surfaces.

Possibility of transmitter to store the settings for more than one model is an important feature. Let's suppose that you have two models, a glider and a helicopter. Adjustments on the transmitter for two different models like this will be quite different. When you take into account that adjustment commands for each of the models may require considerable time (and nerves), it is clear that through this process you do not want to go every time you change the model. If transmitter can store a 10 models, that's fine, but today's transmitters can store a much more. With the more expensive transmitters there are memory cards  that can be removed and inserted into a computer, and setup model on your transmitter .
Also, I should mention  not only every model can have their settings, but also the same model can have multiple "flight modes". For example, expensive and sophisticated competition gliders in F3J category use one mode for start on the winch, the other while flying in thermals, the third as they are landing with flaps, etc.

MODE description
When buying a new radio, salesman will probably confuse you by asking which MODE of the transmitter do you want to buy. There are 4 modes defined 1,2,3 and 4: They are most commonly sold as Mode 1/3 or Mode 2/4. Modes determine the function (command) of the sticks. If you select MODE 1 you will have aileron command and the throttle on the right stick, and the left stick controls the Rudder and Elevator. If you select MODE 2 you will have aileron and elevator controls on the right stick, and the throttle and rudder on the left stick.
This is all because that on throttle stick there is no control that would  return the stich to the neutral position (center), as is the case with all other movement sticks. If this wouldn't be necessary,  there would be no difference between the MODEs on transmitter because the commands on the sticks can be assigned independently.
A better transmitters have the possibility of mechanical switching between MODEs. And those top, expensive transmitters, have software switching, without opening the radio itself.

Control surfaces for the height or depth  (ELE- elevator), tilt (AIL - aileron), direction (RUD - rudder or yaw on the helicopters) and throttle (THR - throttle) are shown below:

The cheapest radio(transmitter) that will meet the needs of every beginner is Turnigy-i6, which also has telemetry data.
It is a 6-channel radio which proved to be quite good for beginner models.
The range of radio is solid 500m, which is quite enough to fly airplanes and helicopters, and even small gliders and quads.
For the price of 50$, it really offers more than enough. With the radio you also get one 6 channel receiver , and the radio has memory for 10 different models.

One of the most popular (and cheap) computerized radio is Turnigy 9x.
For the price of 77$ this 8-channel radio will offer each newcomer  much more than what he will initially need.
Also, the receivers for this radio are quite cheap, so every your model can have its own receiver, and when you decide to fly, it is enough to charge the battery, put it in the desired model and pleasure can begin.

Many people will say that there are cheaper 6 channel radios on the market, that can be bought for 20-30$, but in my personal experience, such radios often lack the delta mix necessary for beginner's model (type ZAGI), and the range is quite questionable. There are cases when a range is hardly up to 50 meters,they are susceptible to interference, and ultimately flying with a such radio can end quite fatal for the model.

Best Buy radio currently is FrSky Taranis.
It is a 16/32-channel radio with all possible options that exist in the market, therefore, telemetry, voice notification, any number of settings, memory for 250 models ....  everything. It uses well-known and extremely resistant ACSST protocol in communication between radio and the receiver, which is quite resistant to all external influences and  that radio swept most expencive radios from renowned manufacturers such as Futaba, Graupner, Spektrum. With this radio and the receiver, you can be sure that the range will be at least 1.5 km minimum. If the conditions are good, range can go up to 2.5 km with this combination.
A nice thing is that the radio has a slot for an additional module if by any chance you already have receivers and models from other manufacturers (different protocols). Just prick the module to the station (such as Spektrum for DSMX or DSM2 protocol) and use it instead of the internal.
Using internal and external module together, you can get 32 ​​channels , which will rarely be needed.

There are many radios from other manufacturers, one that I prefer because ease of use and high quality is Spektrum (by Horizon Hobby).
A 6 channel radio from Spektrum has telemetry, voice and intuitive and easy setup procedure that every beginner will understand, unlike other cheaper radios.

Another benefit (again in the case of the Spektrum) is a pile of finished BNF (Bind And Fly) model airplanes, helicopters and gliders that you can buy, ranging from micro planes and gliders up to large motor planes. BNF models for Spektrum have in themselves already installed Spektrum compatible receiver, such models come complete, and some fully assembled, with batteries and a charger. It is only necessary to charge the supplied battery, connect (BIND) radio with model and flight can start in less than half an hour of opening the box.


  1. Excellent beginners tutorial! I may just add: the more love for this sport you have - the better pilot and constructor you become.

  2. Bravo Gorazd, no one is a prophet in his village .
    Ciao !


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