A radio scanner is a device used to cover a wide range of frequencies. Radios receive signals from the radio stations only. A radio scanner can be used to communicate as well. Unlike the radio stations, it can transmit messages over a broader range of frequencies ranging from 400 – 470 MHz. Because of this feature, a radio scanner may be used for emergency communication, air traffic control, radios, taxis, etc. A radio scanner mainly performs the search function and scan function. Certain information over a certain frequency range would be asked to search. If the result is found within the limited frequency, the information is scanned and received as radio signals. Even in emergencies like fire accidents, or for an ambulance (road clearance) a radio scanner is used. Scanners come in two forms: handheld and base unit. A base unit scanner may be used in homes or workplace and cannot be carried outdoors. A handheld scanner can be used outdoors also. A beginner is advised to use handheld scanners. A beginner should know the basic technicalities of a scanner before proper usage. Most of the time complaints occur due to user errors. It is very important to study the function and control methods of the scanner to prevent user errors.
1. Modes: There are two types of modes in every scanner Am and FM. Use FM for a clearer frequency. In some scanners, FM would be used as NFM or WFM. NFM refers to narrow frequency mode and WFM refers to wide frequency mode. You need to use WFM for listening to commercial radios. The rest can listen tuning to NFM. On advanced scanners, you might find lower sidebands and upper sidebands. These are usually used in ships, aircraft, etc.
2. Squelch: Learn to control your squelch properly. First turn your squelch toward the right until you hear an evident hissing noise. Slowly turn it right back till you hear the distortion stop. This is the exact point at which your squelch is tuned. Do not tamper with this frequency at a later stage.
3. Step size: Adjust your step size to 12.5 kHz for VHF and to 6.25 for UHF.
4. Scan delay: There would be a delay for about 2 to 30 seconds after every once the scanner is searched for new information.
5. Lockout: This is an option in your scanners to lock out or block certain frequencies. There would be certain frequencies that make your scanners stop. This particular channel may be locked out. Even when a search is carried out, there would be certain channels you wish to ignore so that the search is carried out more quickly and efficiently. In such cases, the channel is blocked.