What is a Repeater?
A repeater, simply put, is a base station radio that re-transmits what it receives. By using the power and situation of the repeater, the range of communications is increased. The repeater will maximize the range potential of lower wattage units such as mobiles and portables. For example, two mobiles may be able to communicate via line of sight at a range of 2 to 10 kilometres. By using a repeater, these same two units may communicate 20 – 50 kms. This is accomplished by the repeater re-transmitting what it receives. Therefore, if you can transmit to the repeater site, the repeater will re-transmit using its output power, antenna gain and antenna height to increase the range of communications. As an example, one of our clients is able to talk on a hand held portable radio from the Southern Suburbs, including Fish Hoek to the head office, which is situated in Bellville.
What sort of after-sales support do you offer?
Radio Dot Com is an accredited Icom, Motorola and Kenwood repairer so we offer extensive after-sales support.
We don’t have the budget to buy enough radios. What alternatives are there?
We can tailor a purchasing option to suit your budget and business. It might be ongoing rental from our large fleet of modern radios, rental – leasing or outright purchase.
UHF versus VHF
There are two major formats for two-way radios. They are Ultra High Frequency (UHF) radio and Very High Frequency (VHF) radio. Neither frequency band is inherently better than the other. Both formats are effective ways to communicate with another person so the right radio depends on the application.
The wavelength of a UHF and VHF signal plays a big role in which radio technology to use. UHF has a shorter wavelength which makes it easier for the signal to find its way through rugged terrain or the inside of a building. The longer wavelength of VHF means it can transmit further under ideal conditions. For most applications, lower radio frequencies are better for longer range.
If an application requires working mostly outdoors, a VHF radio is probably the best choice, especially if a base station radio indoors is used and an external antenna is added. The higher the antenna is placed, the further the radio can transmit and receive. One exception to using a VHF radio outdoors is if it is used it in a heavily wooded or rugged area. Under these conditions a UHF radio may be able to transmit better though the terrain (unless the VHF antenna is raised above the terrain).
If the radios are used mainly inside buildings, then UHF is likely the best solution since its shorter wavelength travels through the building better. There are also repeaters that can be installed that relay a UHF signal to increase the communication distance.
A repeater, simply put, is a base station radio that re-transmits what it receives.
A communal repeater is a repeater that uses multiple codes (either tone or digital) to separate users. This allows multiple users to share the repeaters’ resources, therefore the term Communal Repeater.
Communal Repeaters are located on high sites on either tall buildings or mountain ranges.
By using the power and situation of the repeater, the range of communications is increased. The repeater will maximize the range potential of lower wattage units such as mobiles and portables. For example, two mobiles may be able to communicate via line of sight at a range of 2 to 10 kilometers. By using a repeater, these same two units may communicate 20 – 50 kms. This is accomplished by the repeater re-transmitting what it receives. Therefore, if you can transmit to the repeater site, the repeater will re-transmit using its output power, antenna gain and antenna height to increase the range of communications. As an example, one of our clients is able to talk on a hand held portable radio from the Southern Suburbs, including Fish Hoek to the head office, which is situated in Bellville.
RDC is able to offer its clients repeaters solutions owing to the large number of repeaters that we operate as well as out extended network. Solutions can be tailor made for:
-Those that require mission critical communications and cannot afford any delay e.g. armed response
-Users who operate in a localized area e.g. Neighbourhood watch
Trunking is a Radio Communication technique. Unlike the traditional radio communication systems, whereby the different users have been operating on separate radio frequencies or radio channels, radio trunking controls and guides the users toward a free channel.
Trunking permits a large number of users to share a relatively small number of communication paths or trunks. Channel assignment is automatic and completely transparent to the individual users. Finding a free channel is therefore not the user obligation as the system does it automatically.
Trunking is therefore defined as the automatic and dynamic allocation of a small number of radio channels among a large number of radio users.
RadioDotComm is an authorized distributor of Fleetcall and Q-Trunk networks and services.
HOW TO USE A COMMUNAL REPEATER
The manner in which Communal Repeaters are used in South Africa is governed by regulation C4 of the Telecommunications Act No. 103 of 1996:
C4 Technical requirements for the operation of a private communal radio repeater station service
Subject to the provisions of the Act and of these Regulations no person shall operate or use a private communal repeater station unless -Tone signalling is built into all stations in the system: Provided that if the CTCSS signalling method (continuous-tone coded squelch system) is not used, other method of automatic tone control shall be used to ensure that contact with the repeater station is maintained at the end of each message in order to enable the recipient of the message to reply;
b. Each station is equipped with a two-minute forced repeater-release facility: Provided that the forced release shall not be exclusively dependent on the discontinuance of the carrier;
c. The private communal radio repeater has a facility to prevent any user group from re-engaging it within one minute of completing a call;
d. All transceivers have a built-in facility to prevent the transmission of a carrier while the private radio repeater is being used by other clients and by means of which it can be ascertained whether the system is engaged; and
e. The transmitter power is set at the levels as approved by the Authority.