A scanner is a radio that covers a wide range of frequencies than your average radio at home. Communications that you find in everyday use have a single purpose. Like the radio in your car or home is designed only to receive commercial radio stations. On the other hand, radio scanners can receive signals transmitted on a wide range of frequencies.
It allows the users to listen in to a vast range of different communications like air traffic control, emergency services, hobbyists, security guards, taxies, and a lot more.
What does a scanner do?
A scanner has two significant modes of operation that are commonly known as ‘search’ and ‘scan. In search mode, you are searching for any transmissions with a specific frequency range that is specified by the user like 400-470 MHz.
The scanner will quickly scan these frequencies. If it detects a transmission immediately and lets you listen to what it has found, at this point, you can also hold the scanner on this frequency and continue to monitor.
Moreover, you can also store the frequency into a memory channel. you can use them for future reference. That brings me to the next mode on your scanner that is known as a scan.
Once you s filling up your memory channels with frequencies, you can set the scanner to scan the channels. Most interesting is that this mode on most scanners is rapid, so you never miss any action.
Radio scanners can be either portable, with a rechargeable battery, or desktop, like a regular radio. Radio scanners are gaining popularity with consumers. With the massive popularity of NASCAR racing, people now use these scanners at auto racing events. At a typical race, there are hundreds of frequencies that are used.
Some of the recently released radio scanners are capable of tracking municipalities and police frequencies in the 800-megahertz (MHz) range.
Higher-end radio scanners can be controlled by using special software. It helps a lot to the user with the logging of stations as well.
The controls on a radio scanner can vary, but practically all of them have:
- Volume
- Squelch
This is an adjustable control that keeps the speaker muted when a station is not transmitting. It works in all conditions, whether the radio is scanning, searching, or manually stepping.
- WX button
This is more common in new models of radio scanners. This button is a mini-scan of some factory-written frequencies and receives the nationwide NOAA weather broadcast reports.
- Numeric keypad
The numeric keyboard is used for entering frequencies or used for entering upper and lower ranges between two rates. However, the keypad also allows you to enter rates that found during a search.
However, expensive models of radio scanners automatically store frequencies that found during a search
Most radio scanners can receive frequency bands in the 29-MHz to the 512-MHz range. It is essential to know that if you enter a frequency outside that range, you see an error indication on display.
- Search button
It starts the radio scanner on a continuous loop between two frequency limits and allows you to find unknown frequencies within a given range. You can also make a note of the displayed rate or store it at that time, and then continue this search. The instruction manual with a scanner shows what frequency bands are for government, business, aviation, and other users.
- Manual button
The users can manually step through a range of frequencies that are stored in the scanner. Modern scanners have more than 300 channels for storing frequencies in the built-in memory. However, more expensive models have even more.
- Lockout button
The lockout button temporarily disables the radio scanner from stopping on a stored frequency. Radio scanners come with small whip antennas as well as an external antenna connector that enables you to hear more transmissions at a greater distance.
- Delay button
Delay button makes the radio scanner stall for a short duration on a frequency before moving to the next one. It also helps the user to hear the other part of the radio conversation on that frequency.
It is essential to know that radio canners cannot hear everything. The typical consumer-grade scanners are not capable of listening in 900-MHz frequency.
