Number of fixed settings
The number of fixed settings (presets) provided in the car radio equalizer.
The presence of such settings can greatly simplify the adjustment: choosing the right preset is easier than manually adjusting each EQ band. At the same time, presets are often selected by the manufacturer for certain genres of music and have the appropriate names — "Rock", "Pop", "Jazz", etc.; this simplifies the task even more. And the more fixed settings in the device, the wider the choice of the user. In some radio tape recorders, in addition to pre-flashed ones, user presets are also provided — they can be programmed in advance and turned on in the same way as the preset ones.
Line out
The number of line outputs (see above) provided in the design of the radio. It should be noted that usually these outputs use RCA connectors (“tulip”), and the analog format allows only one audio channel to be transmitted through one such. Therefore, to work with a stereo signal,
two RCA connectors are required, and just a pair of such jacks is considered to be one line output - a set designed for one set of stereo speakers. The main difference between this interface and the same RCA used to connect speakers (see above) is that the line output receives a signal from a preamplifier that is unsuitable for feeding to passive acoustics. Such a signal must be sent to active speakers or an external amplifier (whereas the speaker is connected to the output of a power amplifier designed for passive speakers).
Tuner bands
— FM. This term refers to the part of the ultra-short wave (VHF) range ranging from 87.5 MHz to 108 MHz. It uses frequency modulation, which allows you to broadcast music in stereo with a fairly high sound quality, as well as transmit RDS signals (see RDS support). At the moment, most music radio stations in the CIS are broadcasting in this range. The disadvantage of FM is the limited reception area — a maximum of several tens of kilometers from the broadcasting station — so they can usually be listened to within the same city and surrounding areas.
— AM (English amplitude modulation — amplitude modulation) — broadcasting using amplitude modulation. It can be carried out in different bands, but most commercial broadcasts are carried out on medium waves in the range of 520-1610 kHz; most consumer AM receivers, including those in car radios, are designed for the same frequencies. AM broadcasting has a much longer reception range than FM (it can be hundreds of kilometers), but the sound quality is lower, so this format is broadcast mainly by “talk” and news radio stations.
— LW (English long wave) — broadcasting on long waves in the range of 148-408 kHz. Such broadcasting has a reception range of hundreds and even thousands of kilometers, and is almost independent of the time of day and atmospheric interference. It is used mainly at stations of national importance.
— MW (English medium wave) — broadcasting on medium waves in the range of 522-1...720 kHz, in fact — the same as AM (see above).
— SW (English short wave) — broadcasting on short waves, is carried out in a whole set of bands, the lower limit of which is at the level of 2.5 MHz, and the highest — 26.1 MHz. The features of the propagation of short waves are such that they can be received on the opposite side of the globe, but it is not always possible to hear within a few tens of kilometers from the transmitter. Therefore, shortwave broadcasting is mainly used for foreign broadcasts.
— VHF. In this case, not the entire VHF band is meant, but the sub-band 65.9-74 MHz, using the so-called OIRT modulation. In this format, VHF broadcasting was originally conducted in the countries of the Soviet Union and Eastern Europe, but at the moment it is not very popular due to the development of FM. VHF OIRT is technically similar to FM (see above); the main differences are the bandwidth occupied and the inability to transmit RDS signals in OIRT (see RDS support).
