The two way radio is an important tool in may industries, from taxis to security it provides operatives with an instant form of communication for the relaying of important information. Typically the two way radio is available as a handheld device although stationary central devices are also used for more far reaching purposes. The history of this device is an interesting tale of innovation and experimentation.

At the earliest stage the first receivers and transmitters were created to carry message wirelessly. Some argue that it was in 1907 that two way telegraphy started across the Atlantic Ocean as a commercially available communication method. The uses of these devices spread rapidly and by 1912 wireless devices were fitted in the majority of commercial and military ships to allow communication across the seas.

This early equipment however was in no way mobile and usable for transit applications. This all changed however in 1923 when an Australian policeman, Frederick William Downie invented the first portable wireless communication device for patrol cars. As a senior officer in the Victoria Police Force, Downie felt that the existing method of communication that utilised strategically placed phone booths was simply inefficient and unworkable for the purposes of effective crime fighting. Hence he worked towards creating a device that would allow officers to communicate with each other and the headquarters from their cars. The equipment however was still large and cumbersome, reports from the time claim that the radio took up the entire back seat of the Lancia patrol cars.

Technology however rapidly improved and the size of the two way radio was soon reduced. The military were quick to realise the benefits of the device by fitting them into aircraft. This innovation meant that pilots no longer had to drop messages to troops on the ground and instead were able to communicate in real time with other aircraft and commanders. Development continued in both the military and law enforcement spheres. The New York Police Department utilised a system that enabled faster response times while during the Second World War troops used handheld and backpack devices that allowed for greater operational effectiveness.

These early systems however had serious limitations, the most serious being that only one communication could occur at any time. This was because all of the devices used the same frequency; understandably this led to confusion in many cases. The problem was solved however by giving different transmitters their own frequency meaning that systems were linked to a smaller network. Terminology refers to these two systems as 'simplex', the single frequency mode and 'duplex', the multiple frequency mode of operation.

The earliest of these devices required operatives to train and learn Morse code; especially true in the shipping sphere. However the advancement of technology, particularly in the military meant that the transmission of voices became a reality. This subsequently led to more efficient communication and hence greater levels of operational effectiveness. Today devices are simple and easy to use meaning that operatives do not require large amounts of training to utilise the equipment successfully.

From humble beginnings helping the police forces of Australia the handheld two way radio has made life easier for many all over the world. It has not only made the role of law enforcement more successful but has also played an integral part in winning wars. In the modern era it still has a number of applications in the military and police but in many other industries such as retail it is also extensively used. In the world of communication there is no other more important device.