Comparison Syma S39 vs Syma S33

The minimum age for which this radio-controlled model is suitable. These recommendations are rather conditional, but it is still not recommended to deviate from them. "Adult" models 14+ with many adjustments, moving parts and power simply will not be able to master the baby. At the same time, models for the younger age category may not be interesting and boring for older children.

The number of control channels provided in the radio-controlled model.

Each such channel is responsible for a separate control function: the operation of the rudder, elevators, etc. For the simplest models, 2 – 3 channels are enough. Full control requires more channels. In advanced models, additional channels may be provided, the total number of which can reach 6 or more.

The capacity of the battery supplied with the electric motor model (see "Motor"). Indicated only for variants using branded batteries (see "Battery type"), measured in ampere-hours: 1 Ah corresponds to the capacity at which the battery is capable of delivering a current of 1 A for 1 hour.

The higher the battery capacity, the more time the helicopter can spend in the air, usually. However, the practical time of operation on a charge is largely determined by other characteristics of the machine — dimensions and weight, engine model and power, etc. Therefore, in most cases, this parameter plays a purely reference role, and only helicopters that do not have any significant differences in other characteristics (and even then very approximately) can only be compared in terms of battery capacity.

Operating voltage of the battery supplied with the helicopter. For models for AA cells (see "Battery type"), this voltage is not indicated — the specification of such cells assumes a common voltage standard, about 1.5 V. In other cases, this data is not particularly important for everyday use, but it may be useful if you you need to pick up a charger, a spare battery or a battery to replace a damaged one, but you don’t have data on the battery model (see below).

Operating time of an electric powered helicopter (see "Engine") on one battery charge or on one set of batteries. This parameter is rather conditional and approximate: it is usually indicated for optimal operating conditions, with a uniform low load on the engine (most often for hover mode), and when using replaceable cells — for high quality batteries. Accordingly, in fact, the operating time may differ markedly from that stated in the specifications. Nevertheless, this indicator quite reliably describes the battery life of the car, and different models can be compared according to it.

Capable of charging the helicopter battery from a standard USB port. This function is convenient primarily due to the prevalence of the USB standard: it is used in the vast majority of modern computers and laptops as a data transfer interface, and in portable electronics it is also used as a power source for charging batteries. Thus, a model with this feature can be connected for charging to computer equipment — or to any 220-to-USB network adapter. This is more convenient than using a specialized charger (which can also be lost). However the current power during such charging is relatively low, which is why it is poorly suited for powerful batteries.

The greatest distance between the remote control and the helicopter at which the remote control transmitter is still able to guarantee normal controllability of the model. Note that official specifications usually provide data for perfect conditions: full battery charge, no obstacles in the signal path, extraneous interference, etc .; in fact, the range may be somewhat less. However, by this parameter it is quite possible to compare different models with each other.

The higher this indicator, the further you can let go of the helicopter from the remote control, the less often you have to move to keep control. However, a large range means not only a long range as such — it also speaks of a good signal penetration, its ability to pass through various obstacles. At the same time, powerful transmitters require appropriate power and large antennas, which affects the weight and dimensions of the console.

The frame is the base of the helicopter; it is on it that the engine, mechanisms, electronics and body are installed. It may have the following structure:

— Team. This category includes frames consisting of separate parts on detachable joints — for example, bolts. Other things being equal, they are considered less reliable than solid ones, because. connections are usually the "weak point" of the design; however, for simple flights, this reliability is quite enough, and prefabricated frames are somewhat cheaper. This option is found mainly in entry-level models, as well as in inexpensive middle-class cars.

— Whole. A frame that does not have collapsible joints and is made in the form of an integral structure. Theoretically, this option is able to provide high strength, making it suitable even for professional-level machines. However, in fact, a one-piece frame in itself is not an indicator of a high class model — it is found among helicopters of all price categories, and the quality of the structure, usually, directly depends on the cost.

General dimensions of the model. Note that the length and width are indicated only for the fuselage, excluding the main rotor. However, for ease of transportation, the blades are often made removable or folding.