Showing posts with label Repeaters. Show all posts
Showing posts with label Repeaters. Show all posts

Friday, 9 November 2012

Walkie Talkies – A Compaq and Easiest Means of Sharing Messages

Walkie talkies are the handheld tools popularly known as two way radios also. This system functions on the principle of half duplex, wherein messages can be sent and received one at a time. Users have to press the button present in walkie talkie to send the message and have to release it to receive the message. Their functionality is not bound to any time duration or size duration. Users can send longer messages also. Walkie talkies are mostly used in malls, defence offices, commercials and also for personal use in large distances.

If we recall the old days, our parents use to make trunk calls. You must have wondered ample of times thinking about the meaning. Trunk calls follow Trunking systems wherein from single frequency, multiple connections can operate. This enables easy and secured sharing of information within the organization. Though there are many modes of communications available in the world due to technological development, the base for these modes remains the signals of the network. There is a huge indoor and outdoor coverage problem in rural or congested areas.  Repeaters amplify the existing signals from the nearby base transceiver system and provide fair coverage and voice quality.

Continuous growth have evolved the production of DMR Radio (Digital mobile radio) providing services of optimum privacy to the confidential conversations and also providing good coverage and voice quality. Terrestrial trunked radio (Tetra) is yet another radio derived from ETSI. It works on two RF’s (radio frequency) and used mainly by government projects, hospitals and commercial offices.

Tuesday, 31 July 2012

The Trunking Systems and the Working of Other Radio Systems for Security and Entertainment


In the past when the mobile phones were not available and it was not within everybody’s means to have landlines with the STD and ISD connections. The Telephone Exchange used to offer the use of trunk calls, to where ever you needed.  This was possible with help of the Trunking systems.

The idea of trunking , in which a main telephone  switch board with many connections that use a same  sound wave length  can use instead of each one being allotted a different personal  link. A miniature form of the trunking system can be seen in offices where a telephone operator and intercom systems are used. 
With the use of the two way radio handset, called walkie talkie, nobody can complain about the communication amongst the working team or other group members. But, yes, one has to watch the area coverage by the walkie talkies. The walkie talkies were originally designed for the exclusive use of the police and security force.  Later on the commercial models of the same were sold in the market for the use in many professional fields like construction.

The PMR radios were replaced with an advanced version called DMR radio or the digital mobile radios. The DMR offers talking, information and various other facilities and aspects. The chief motto of the DMR is to offer an easy to handle, minimum price factor and inter usable feature with all the other brands.  

Instead of using many radio sets and other connecters to improve the reception range of the service repeaters are used at intervals to increase the area of reception of conversations, information and other features. Tetra or the terrestrial trunked radio is movable radio working on two frequencies. Tetra was patterned mainly for the use of various departments of the governing bodies and other SOS services. 

Wednesday, 4 July 2012

Development of Digital Two Way Radios


Information and Technology has developed rapidly within last decade and now in 21st century the means of communication has reached a level where there is no barrier to it. Now people are free to use individual network lining and can avoid any bad audio quality or fading problems. There are trunking systems that allow better radio frequencies without any line breakage or fading. These systems are comparatively cheaper to older individual lining system.

The digital radio broadcasting technologies now has developed better systems and networks for digital two way radios giving the PMR radio better options to connect and work. These are 2nd generation radio systems and as they are two way, you can both transmit and receive message. These radio systems are most useful for security agencies for individual and mass protection. Police, fireman, military and such security agencies use these types of radio mobile systems. 


These systems can be of different types, depending upon their use they can be mobile, stationary base, and walkie-talkies. To work these types of radio the networking system needs different levels of support and backup. Such supports should be provided without any interruption and for this a direct satellite network connection is also maintained specially in the case of military and high level security systems. In mountain areas the network gets blocked by different blocks and frequency mix and to solve this problem repeaters are used. A repeater takes the message and retransmits it to higher level so that the message goes without any interruption to long distance.

Digital Mobile Radio (DMR) is an upgraded open digital radio system for Professional Mobile Radio (PMR) and to support them the ETSI (European Telecommunications Standard Institute) made Terrestrial Trunked Radio (TETRA) system. It is a two way receiver and is best for mass security purpose, because with this system one can transfer and receive message from point to point and from point to multipoint and vice-versa. These radios can also be operated hands-free and so can be referred as covert radio

A digital licence free radio is latest addition to two way radio system that gives you charge-free communication facility. This system is used for private use and they work with the help of repeaters and internet. The only drawback of this radio system is that they work only within few kilometres range that too if the area is clear and viable for PMR and DMR frequencies.