The History of Police Scanners - Essay Example

The History Of Police Scanners and The importance of police scanners in the modern world cannot be underestimated. The demanding job of the police sector includes controlling crime, maintaining order, and providing intricate array of services such as responding to emergencies and controlling traffic flow, thus there was need of an effective form of communication. The form of communication would help ease the constraining difficulties in undertaking police duties. Police scanners, which are also called radio scanners, have been used in tuning and monitoring wireless radio communication via different radio channels. In the modern era, the devices have helped in promoting security, and enhancing quick responses to emergencies. Additionally, police scanners play a crucial role in journalism and crime investigation centers. Therefore, through the application of the police scanners, the world has been compressed to a smaller area in terms of space and time. However, the evolution of police scanners has undergone tremendous changes since their invention. This essay will cover in details the history of police scanners. The idea of using receivers and transmitters began in the early 20th century where 2-way telegraphy traffic was in commercial use in the Atlantic Ocean. As early as the beginning of the 20th century, military and naval warships were applying the 2-way form of communication through the installation of both transmitters and receivers in the ships. Therefore, a two-way communication enabled ships that were apart in distance to communicate effectively. Australia.gov states that the Victorian Police were among the first sectors to invent portable 20-way radio in Australia in 1923; they installed the devices in police cars and used them to replace the previous telephone boxes that were cumbersome and at times inefficient in communication. However, the initial sets were also bulky and occupied large spaces. For instance, they occupied the entire back seat of the Lancia patrol cars. According to Scanner Master, police departments implemented the aid of tunable radio receivers to monitor police channels using a low frequency at the receiving end of the AM radio dial around 1700 KHz. They used this frequency to broadcast to their patrol cars regardless of the distance, and the communication equipment proved effective in transmitting signals. Police and fire departments used the FM radio channels that operated between 40 and 155 MHz in the 1960s, which motivated radio developers to develop scanners that could perform rapid tuning functions by searching for neighboring radio channels for frequency activity. The early scanners could only search either four or eight channels hence people had to purchase crystals for particular radio frequencies within their surrounding local departments in order to monitor the channels. Scanners emerged from previously invented fixed-frequencies radios that only could only receive, or transmit a single frequency at a time. Radio Scanner guide point out that the first models of scanners emerged during the time when citizens band radios were in use during the 1970s. The Citizen Band radio idea had occurred earlier where journalism editors such as Herbert Brooks emphasized on the need for a low-power portable UHF rig, which had not been occupied by commercial and amateur services such as radio-auto-horn and radio model controls. During the end of the Second World War, a drafted project was presented at the FCC frequency allocation hearing, which proposed a band of frequencies that could be reserved for the veterans. The suggestion was based on the fact that most of the veterans returning home had technical knowledge and skills of operating a personal-communication industry. Only two classes of CB service existed namely class A and B, which differed in their functionality depending on their frequency. Class A implemented complex technical standards, which effectively operated with up to 50 watts whereas Class B applied simple standards of technicality thus their frequency strength was restrained to smaller ranges and 10 watts of power. John Mulligan was among the first radio engineers to be assigned the band where he created 2 types of radios that operated in the 460-MHz range, which were used for experimental testing and gave back the test results to the industry. The radios were able to effectively transmit and receive signals on 5-miles distance. Firestone Tire Company was given an experimental license W1ØXXD, which operated on 27.255 MHz, which used 2 three-watt transmitters; these radios established the grounds for newer inventions such as the more sophisticated modern Citizen Radio gears. Additionally, other companies were also established that specialized in the developments of these radio devices. For, instance Gross established the Citizens Radio corporation, which produced 2-way radio for private use. Although the two classes developed by Gross did not trigger a massive market reception, the invention laid an innovation platform for later manufacturers. During the beginning of 1980s, keyboard scanners began replacing the crystal scanners as technology advanced. Most of the lower end scanners had between eight to twenty channels and lacked a mode of searching. A number of the scanners could only display the number of the channels but the frequencies could not be displayed. The emergence of higher end scanners established a new mode of scanning channels. According to the Radio Scanner Guide, the new models such as the PRO-2004 could now scan over three hundred channels in ten banks of scanning. They could also cover 25 to 520 MHz and 760-1300 Mhz. Police departments especially those located in the modern cities started migrating to the new 800 MHz. Around the middle nineties, police departments all over the larger towns had migrated to the 800 MHz . The move was made in a strategy to reduce the number of scanner listeners and instances of spying on police activities. The trunking method in which a particular frequency would be set from a number of frequencies that were transmitted by a user, was the most implemented method of scanning. Cheap scanners on the 800 MHz band started emerging, which could follow trace conversations in a system using the trunking method. An example of such a scanner was Uniden BC235XLT, which contained approximately three hundred channels in ten banks. The scanner faced some limitations such as it could not hear more than one trunked system at any given time. However, beginning the 21st century many police departments shifted to using digital voice methods that scanners could not receive. Uniden introduced two models, BC25OD and BC785D, which had the feature of hearing the new systems when an optional digital card was inserted. The new models had a limitation of only following systems that were in mixed-mode, this limitation was fixed by the handheld PRO-96 that was produced by Radio Shack. The current digital scanners are very expensive in contrast with the previous cheap analog scanners. Works Cited “All about Scanners.” Scanner Master.com. Web. 20 July. 2014. “History of Scanner Radios.” radio-scanner-guide.com. Web. 20 July. 2014. “Radio in Australia.” Australia.gov.au. Web. 20 July. 2014. Read More