Comparison Philips TAR-2509 vs Panasonic RF-D15

A type of tuner used in radio receivers.

- Analogue. Tuning to the desired frequency in such tuners is carried out using the wheel. This scheme is considered more convenient than digital trim (see below), but the accuracy of analogue regulators is lower. This can make it difficult to use the receiver with numerous stations in a small frequency range (especially for FM broadcasts in large cities). In addition, the analogue tuner "does not know how" to memorize stations.

- Digital. The direct tuning of the tuner in such receivers is performed by an electronic circuit; the user only sets the desired frequency using the increase / decrease buttons or, in advanced models, from the numeric keypad. These tuners are somewhat less convenient for manual tuning, but they do a good job of fine tuning. Also, many receivers with digital tuners have the function of storing stations (see "Station Memory"), automatically searching for all available stations, etc.

— FM. The most popular broadcasting range among radio listeners today is primarily due to the fact that the vast majority of music stations broadcast in it. This is due to its features: FM uses frequency modulation, which makes it possible to broadcast sound with a fairly high sound quality, and even in stereo format. In the frequency band, the term "FM" usually refers to the 87.5 MHz to 108 MHz portion of the VHF band, although the range of individual receivers may vary. The disadvantage of FM is the limited range — within the line of sight (up to several tens of kilometers), which has secured the reputation of "urban" stations for FM stations.

— AM. Formally, this designation is not a range, but a type of modulation: "amplitude modulation" — amplitude modulation. In consumer radios, AM most often means the medium wave range of about 520-1610 kHz. Such waves have a propagation range of hundreds of kilometers, but the sound quality in this case is somewhat worse than that of FM, and therefore the AM band is mainly used by radio stations of the “conversational” genre (for example, news or journalistic).

— SW. Broadcasting on short waves (short wave) in the general range from 2.5 MHz to 26.1 MHz, divided into a number of separate sub-bands. Sound quality is average. Short waves are able to reach the opposite side of the Earth, but immediately outside the line of sight of the transmitter, a “dead zone” is formed, several...tens of kilometers wide. As a consequence, SW is commonly used for overseas broadcasts.

— DAB. Abbreviation for Digital Audio Broadcasting, i.e. "digital broadcasting". This term describes the key difference between this range and those described above: broadcasting in it is carried out not in analogue, but in digital format, the MP2 codec is used for transmission. This gives a number of advantages over traditional transmitters — in particular, a greater range with less power and high quality of the broadcast sound. In addition, this sound is practically not subject to distortion: weak interference does not affect its quality, and when the transmitter power is critically reduced, the signal is not distorted, but disappears entirely. The latter, however, can be written down as disadvantages; but the really significant drawback of this option is perhaps its low prevalence (so far) in the CIS countries. Technically, such broadcasting can be carried out in any band above 30 MHz, but in fact several options are used (depending on the country) related to the VHF band.

— DAB+. An updated and improved version of the DAB standard described above. It has all the characteristic features of digital broadcasting, and differs from its predecessor in higher sound quality at the same bit rates — both due to the use of a different codec (HE-AAC v2), and due to the use of more advanced noise correction algorithms. DAB+ broadcasts cannot be received on DAB receivers: at best, this will require a firmware update, and at worst, you will have to change the receiver itself.

Number of stations, i.e. certain fixed frequencies, which can be stored in the receiver's memory. This greatly simplifies tuning: by fine tuning the frequency once, in the future you can turn on the desired station by simply selecting it from the list (and in some models, it is enough to press a separate button once). The memory is usually found in receivers with a digital tuner (see "Tuner type").

The Radio Data System RDS technology is used primarily in the FM band; it allows, in addition to the sound signal, to transmit additional textual information by radio — for example, the names of broadcast compositions, announcements, advertising messages, etc. Accordingly, to display this information, the radio receiver must be equipped with a display.

— Bluetooth. Wireless technology for transmitting sound from mobile phones, tablets, etc. Allows you to connect a device wirelessly at a short distance from the signal source. The quality and overall capabilities of Bluetooth depend on its version:

— Bluetooth 4. Each version brings improvements over the previous one. In version 4.0, three standards were effectively combined: traditional Bluetooth, high-speed channel, and energy-saving mode for small amounts of data. This allowed for optimized channel use and battery consumption. Version 4.1 enhanced resistance to interference when working near 4G LTE modules. Version 4.2 mainly introduced general improvements in speed and security.

— Bluetooth 5.0. One of the most important innovations of the Bluetooth 5.0 standard was the expansion of BLE ("Bluetooth Low Energy") capabilities: if necessary, the device can increase range by reducing speed, or speed up transmission by reducing range. Moreover, several improvements related to simultaneous operation with multiple connected devices were introduced.

— Bluetooth 5.1. A significant upgrade in version 5.1 was the ability to precisely position the signal transmitter (receiver). Whereas previous versions could only determine distance, version 5.1 can also determine direction. This improved navigation function, which enhanced the operation of smart home systems, connected device search, etc. Additionally, improvements a...gain touched on energy consumption savings and simultaneous operation with multiple connected devices.

— Bluetooth 5.2. The next update after 5.1 in the Bluetooth 5 generation. The main innovations in this version were several security improvements, additional energy consumption optimization in LE mode, and a new audio signal format for synchronizing parallel playback on multiple devices.

— Bluetooth 5.3. The Bluetooth v 5.3 wireless communication protocol was introduced at the beginning of 2022. Innovations sped up the channel negotiation process between the controller and the device, implemented a quick switch function between low-duty cycle and high-speed mode, improved bandwidth and connection stability by reducing susceptibility to interference. In the event of unexpected interference in Low Energy mode, the channel selection procedure for switching was accelerated. The 5.3 protocol does not present fundamental innovations, but a number of qualitative improvements are apparent.

— Bluetooth 5.4. Introduced at the start of 2023, this version increased the range and data exchange speed. Also, improvements were made to the BLE energy-saving mode in Bluetooth v 5.4. This protocol uses new security features to protect data from unauthorized access, offers increased connection reliability by selecting the best communication channel, and prevents connection losses due to interference.

— USB-A. The presence of a USB-A port allows connecting USB drives, mobile phones, MP3 players, and other similar peripherals. Accordingly, such models have a built-in player and allow connected gadgets to be used solely as storage devices.

— Card Reader. Like the above-mentioned USB-A, this item implies the presence of a built-in player. And a card reader allows using memory cards as storage on which songs will be recorded.

— Line Input. An input for transmitting sound in analog format. Through such an input, you can connect an external signal source — for example, an MP3 player — to a radio receiver and listen to music through the receiver's speakers. Despite the development of digital standards, the line input remains one of the most popular connection interfaces.

The maximum power output of the receiver speaker(s) in normal operation, without overload. The higher the rated power, the higher the sound volume, but louder devices and energy require more.

The maximum power output of the receiver speaker(s) in normal operation, without overload. The higher the rated power, the higher the sound volume, but louder devices and energy require more.

A connector for connecting headphones in radio receivers, most often a standard 3.5 mm mini-jack. Headphones can come in handy when the sound from the main speaker might disturb others, or in noisy environments where an external speaker doesn't do well.

The format in which the time is displayed on the clock face.

— 12 hours. A format that enumerates individual hours (time intervals) from 1 to 12. Since there are 24 hours in a day, this numbering covers only half of the day. This option is traditional for hand dials (see "Dial type") — historically, the full circle of the hour hand corresponds exactly to 12 o'clock, and it is from this principle that both watchmakers and watch users around the world today proceed. However, it can also be found in other types of dials. Theoretically, this option may require clarification — roughly speaking, "7 o'clock — in the morning or in the evening?" — however, in the vast majority of cases, the answer to such a question is clear immediately, from the context of the situation. But when using an alarm clock (see "Functions / Capabilities") in such a watch, you have to be especially careful: if, for example, at 6 pm you set the signal time to 8 am, the alarm clock will go off at 8 pm, because the clock itself "does not distinguish" between morning and evening.

— 24 hour. A full 24-hour format, provides numbering of hours from 1 to 24 (more precisely, from 0 to 23, because exactly 24 hours are considered zero of the next day). Thus, when looking at the clock, in principle, there is no question whether we are talking about the time of "morning" or "evening": for example, 7.00 will unambiguously correspond to morning, and "7 pm" will be designated as 19.00. At th...e same time, we note that such clarification can be provided in other ways — namely, the 12-hour scale, which has additional indicators AM (ante meridiem, "before noon") and PM (post meridiem, "after noon"). Therefore, models with such modified 12-hour scales are also classified as 24-hour models in our catalog. This format is used in all types of dials, except for arrows.

— 12/24 hour. This category includes watches that have the ability to switch between a full 24-hour clock and a 12-hour clock with "AM/PM" qualifiers. Formally, both of these types of scales are 24-hour scales (and are described in detail in the relevant paragraph above); the same designation is used to emphasize the possibility of switching formats.