Frequency range
The FM frequency range supported by the FM transmitter.
For normal use of the device, it is necessary that at least part of this range coincides with the tuner range in the car radio, and that there is no full-fledged FM station broadcasting at the selected frequency. However, most modern FM transmitters cover frequencies of the order of 88 – 108 MHz, this is quite enough to find a suitable frequency.
Screen
The presence of a display in the design of the FM transmitter.
Various additional information can be displayed on
the display : the set frequency, the signal source used, the name of the song being played, etc. This greatly simplifies device management.
Card reader
A slot that allows you to install memory cards in the FM transmitter and play music from them. Most often, card readers are made for SD or microSD form factor cards; however, both varieties have several variations (SDHC, SDXC), so before using such a transmitter, it's ok to clarify which varieties the
card reader is compatible with.
Media support
File formats supported by the FM transmitter.
Almost all models support the MP3 format, which is the most common modern digital audio format. Some devices are also capable of working with WMA — this is also one of the main formats, but for a number of reasons it is used much less often. And even less common is compatibility with WAV — this format provides higher sound quality, but with FM broadcasting this advantage is lost, and the files themselves take up noticeably more space than MP3 and WMA.
24V support
Possibility of operation of the device with automobile networks with a voltage of 24 V.
Such tension is found in heavy equipment — in particular, buses and main tractors (“trucks”). By default, FM transmitters are usually made for the 12-volt on-board networks of cars; therefore, for
installation in a 24-volt network, you need to choose a model where this possibility is directly stated.
