Comparison Logitech Pebble Keys 2 K380s vs Logitech K380 Multi-Device Bluetooth Keyboard

A version of the "blue tooth" technology for connecting the wireless keyboard to other devices from the outside as a manipulator. The higher its serial number, the more stable and noise-proof connection is provided. At the moment, Bluetooth v 5 is the most advanced standard in keyboards.

— 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 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).