Comparison Logitech Wireless Touch Keyboard K400 Plus vs Gembird KB-P4

The wireless connection range provided by the keyboard (see "Connection type").

Almost all modern wireless models function reliably at a distance of at least 2-3 meters. Therefore, you only need to pay attention to this parameter if the keyboard will be used farther from the computer. When evaluating the range, keep in mind that it is given for ideal conditions: no interference or obstacles, a fully charged battery, etc. In practice, the actual range might be somewhat shorter, so it's advisable to account for a margin when selecting a model. Nevertheless, the stated range can give a good indication of the practical capabilities of different models and help in comparing them.

Traditional keyboards are divided into three main varieties — full-size, compact and ultra-compact. The main difference between them is that full-size models have a Numpad — an additional block with numeric keys and arithmetic signs. Compact models, respectively, do not have a numpad, and in ultra-compact models, the arrow block is either completely absent or located under the Enter key in the form of very small keys.

And full-size, and compact, and ultra-compact keyboards can have different types of layouts. At the same time, the arrangement of letters and numbers above the letters in all types of layouts is the same, the differences are in the shape and position of additional keys (special characters like backslash, system control, modifiers like Shift and Alt, etc.). Here are the most popular options:

— ANSI. The "American" layout format, the distinguishing features of which are, in particular, the same width of both Shift keys, the same labeling and assignment of the Alt keys, the single-row Enter key and the backslash located above it (which is often made slightly longer than the standard key).

— ISO. "European" layout format. The Enter key occupies two rows, while at the top it is slightly longer than at the bottom; the left Shift is shorter than the right one, there is a...backslash next to it; next to the bottom of the Enter may be a second backslash or other special character key; the right Alt is designated as Alt Gr and is intended for entering additional characters in European languages.

— K.S. The "Korean" keyboard layout provides a double-row Enter, as in the ISO described above, however, in this case, the lower part of the Enter is made longer, and not the upper one. The backslash is above Enter, next to Backspace, and Backspace itself is the same length as standard keys (that is, noticeably shorter than in other layouts).

— JIS. Keyboards with a "Japanese" layout have a double-row Enter with an increased length of the upper half — like the ISO described above. However, in this case, the backslash is not located on the left side of the keyboard, but on the right, next to Enter (where an additional symbol key can be located in ISO). Additional character keys may be provided — next to Backspace (as in KS) and/or to the left of the right Shift. In addition, the right Alt can be formatted as Alt Gr.

In addition to compact and full-size, there are also non-traditional keyboard formats:

— Numpad. Separately made block of numeric keys. With the help of such a device, you can, in particular, turn a compact keyboard into a full-size one. Among other things, this combination can be useful for travel: packing a Numpad separately from the keyboard is easier than finding a place for a full-sized "board". Another option for using the Numpad is to connect to a cash register, terminal, etc. to work as a calculator keyboard or in a similar capacity.

— Keypad. A specialized device in the form of a small (approximately 15 – 20 keys) keyboard under one hand; usually, it is complemented by an arm rest, and often also by side buttons for the thumb. Such devices are especially convenient for games and are mainly used in them — certain game actions can be attached to the keypad buttons (including those that are usually implemented through the menu or a key combination on a standard keyboard). The keypad can both complement the main keyboard and serve as a completely separate game pad.

— Non-standard. Non-standard format keyboards that do not belong to any of the varieties described above. The specific design and use of such devices may vary. So, these can be game models in the form of the left half of a standard keyboard (this part is mainly used in games); ultra-compact models for tablets (see "In the direction"); keyboards for TVs, supplemented with special buttons and designed to be held in two hands in the manner of a gamepad, etc.

— Membrane. The name of this type is due to the fact that the contacts under each key are made in the form of two membranes — conductive disks on a flexible film. The return of the keys to their original position after pressing is ensured by the elasticity of the membranes. This design is characterized by low cost and low noise level; in addition, such keyboards are quite resistant to liquid spills (although this is still not recommended). Of the shortcomings, it is worth noting the relatively low durability — 3-4 times lower than that of mechanical ones. In addition, as the keys of this type wear out, the force required to press decreases, they begin to “fall through” under the fingers (“fatigue effect”).

— Mechanical. In this design, springs are used to return the key to its original position after being pressed. Mechanical keyboards are considered more advanced than membrane keyboards: they are more reliable and durable, almost do not lose properties as they wear out, and give a clear tactile feedback. The overall noise level is often higher than that of membrane ones, however, many attribute a characteristic click with each press to the advantages of such models; in addition, completely silent mechanical switches are also available. But of the unequivocal disadvantages, one can name the high cost and sensitivity to spilling liquid (although a mechanical keyboard can also be made waterproof)....r>
— Optical-mechanical. A variation of the mechanical keyboards described above, in which each key is equipped not with a traditional pair of contacts, but with an optical switch in the form of a sensor that receives an infrared beam; when you press the key, this beam is blocked, which serves as a signal for operation. One of the key advantages of such switches is a very high response speed (fractions of a millisecond); this moment is not critical for domestic use, but it can be fundamental for gamers-enthusiasts and e-sportsmen. In addition, the absence of electrical contacts that are prone to wear and oxidize has a positive effect on durability. And although initially the “optics” are more complicated than classic systems with contacts, however, in gaming keyboards, optical-mechanical switches are often even cheaper than pure “mechanics”. And the fact that this option is relatively rare is primarily due to the fact that optical technology appeared not so long ago and is only gaining popularity.

— Membrane + mechanical. A layout in which most of the keys have a membrane design, and some, the most "responsible" ones, are mechanical. About the features of both options, see above, and a similar combination of them is found mainly in gaming keyboards. In this case, the "mechanics" are usually used on the traditional combination of WASD plus on the surrounding keys Q, E, R and F.

— Mechanical-membrane. A hybrid design that combines elements of mechanical and membrane keyboards (see above for more on both). In this case, these features are combined in each individual key. Usually, under each button in such keyboards there is a membrane, however, inside this membrane is not just a pair of contacts, but a mechanical spring system. Thus, this design combines the advantages of both options. At the same time, mechanical-membrane systems are very expensive. Therefore, their main scope is high-end gaming keyboards, and even among such devices this option is quite rare.

— Scissor. A slightly modified version of membrane keyboards (see the relevant paragraph), in which the flexible membrane on each key is supplemented by a two-piece mechanism fastened together in the form of scissors. One of the main features of scissor keyboards is the low key travel (noticeably lower than that of membrane keyboards). Also, this design is less demanding on accuracy, it allows you to achieve a clear pressing regardless of where the finger hit — in the centre or on the edge of the key. The service life of the "scissors" is large; they are more difficult to clean, however, they become dirty much more slowly than "membranes". Among the disadvantages of this option, a slightly increased noise level during operation can be noted — due to the clicking of scissor mechanisms.

The number of additional keys provided in the design of the keyboard.

Such keys do not belong to the standard layout and are intended for quick access to specific functions or individual applications — for example, to control the media player or open mail with one click. This function is convenient because commands from additional keys are usually recognized by the system regardless of what is on the screen — thanks to this, for example, you do not have to close the text editor to switch tracks in the player.

Note that in this case we are talking about individual keys that have a strictly defined purpose and corresponding markings. Programmable buttons, the Fn key (see below) and the functions of the main keys implemented through Fn are not taken into account in this paragraph.

The colour of the Cyrillic letters printed on the keyboard.

This colour is usually chosen so that the letters are clearly visible. This point does not affect the functionality of the keyboard, and the choice in this case depends mainly on personal preferences. However, there is also a practical point: for inexperienced users who have not mastered touch typing, it is desirable that the letters stand out as much as possible against the background of the keys.

Transparent letters are a separate case — they are used in keyboards equipped with a backlight (see below), due to which such characters, when the backlight is on, are visible even in the dark.

Volume control methodprovided in the keyboard (if such a possibility is provided at all).

— Through Fn. Adjustment using the Fn key (see above): increasing and decreasing the volume is carried out by simultaneously pressing Fn and one of the main keys of the keyboard (usually from the F1 — F12 row), The main advantage of this control is that it allows you not to overload the keyboard with additional controls — this, in turn, has a positive effect on the dimensions and cost. The disadvantage is the need to simultaneously press two keys, which is not always convenient.

— Additional keys. Control with additional keys specially designed for working with volume. A very convenient and practical option: additional keys are usually clearly labeled, while they take up less space and are cheaper than a wheel or a touch slider (see below).

— Wheel. Control by means of a mechanical wheel, the rotation of which up and down or left and right provides a change in volume. A fairly user-friendly option — visual, intuitive and accessible even blindly. At the same time, the wheel can take up quite a lot of space, and it significantly affects the cost of the keyboard.

— Touch slider. Management using a touch surface, the movement of a finger in one direction or another. The sensor takes up minimal space, looks neat...and generally fits well with the overall design of the keyboard, but it is not cheap. Therefore, this option is extremely rare, mainly in high-end gaming or multimedia keyboards.

The type of power used in wireless keyboards. It can be a replaceable battery or its own built-in battery.

As replaceable batteries in modern keyboards, batteries or accumulators of the AA (“finger”) or AAA (“mini-finger”) format can be used. The main advantage of this power supply is the ability to quickly replace dead batteries with new ones — if there are any left, a few seconds are enough, and the keyboard is ready to work again. However, batteries are often not included and must be purchased separately. In addition, anyway, you have to buy new batteries as the old ones wear out — or fork out for rather expensive batteries and, possibly, a charger.

Built-in battery, in turn, relieves the user of the need to purchase batteries. On the other hand, in the event of a discharge, such a battery cannot be quickly replaced, and the only option to continue working is to charge it, which can take quite a long time.

The operating time in this case is quite approximate: it is indicated for a certain average mode of use. The actual battery life may turn out to be either less or more than the claimed one, depending on the specifics of the application; in addition, the quality of a particular brand of batteries greatly affects the operating time. Nevertheless, this is a fairly reliable indicator, it is quite possible to evaluate different models and compare them with each other: the difference in the claimed operating time is usually quite consistent with the difference in real battery life when using batteries of similar quality.

It is worth saying that modern battery-powered keyboards have pretty solid battery life, measured in months; in the most "long-playing" models, the operating time is about 36 months (that is, 3 years).