Repeaters
A radio repeater is a base station radio with a large antenna and is normally sited in an advantageous position on top of a hill or a high mast. Repeaters are capable of receiving a signal on one frequency and simultaneously transmitting it on another, usually in the same band. This is very useful because it means an amateur operating a low power radio can transmit on the repeaters input channel and the signal will be re-transmitted on the repeaters output frequency. In effect the receiving and transmitting coverage of the low power station, e.g. a mobile transceiver or handheld radio, becomes that of the repeater thus greatly improving the range over that of unassisted, simplex operation.
A high standard of operating ability and courtesy is necessary to ensure proper use of a repeater. Because repeaters are unmanned relay stations they utilise an automatic system to control their operation. In the UK and Ireland this automatic system requires the operator to send a short 1750Hz tone burst to activate the repeater before transmission can begin. (Some repeaters now require a CTCSS sub-audible tone to be sent for activation purposes, whilst others can be accessed by carrier only). Repeaters are to be found in the 70 Cms, 2, 6 and 10 metre bands.
A list of all VHF/UHF repeaters in Ireland (North and South) may be found on the IRTS website.
A list of repeaters and link stations located in, or accessable from, Northern Ireland may be found here.
A new 70cms repeater, GB3DX, is shortly due to come into operation in the Derry/Londonderry area.. The output frequency will be 433.300MHz and the input on 434.900MHz. Access will be by meansof CTCSS tone 110.9. The repeater will be located at IO65ha and ultimately offer full 24 hour internet coverage via Echolink and the Ireland Conference.Full details are available here
A new repeater (GB3CP) has also come online in South Fermanagh. The frequency of the repeater input 145.1375 Tone 1750Hz/110.9Hz . Output frequency 145.7375. It was installed on Carnmore Mountain between Fivemiletown in County Tyrone and Roslea in County Fermanagh. The repeater's actual location is in County Fermanagh.
A 6 metre repeater GB3TY is now operational from Carrickfergus. The output frequency is 50.780Mhz and the input is on 51.280Mhz. The repeater is accessed by CTCSS tone 110.9.
The GB3LY repeater was replaced in 2008. This is now a 12.5kHz machine which requires narrow deviation and either CTCSS or 1750 toneburst to activate. Full details of the changes to this repeater and how to access it may be found at www.echoireland.com
The first 10GHZ FM voice repeater in the United Kingdom came on the air on 14 March 2008. GBTC is sited in Lanarkshire and operates on a channel pair of 10371.1Mhz in and10471.1Mhz out. CTCSS tone of 103.5HZ or 1750Hz tone burst is required for access.
Repeaters may also be linked together or connected to over the internet using voice over IP (VoIP). Echolink allows hams with computers to connect to repeaters anywhere around the world (see Internet Linked Stations page) and The Internet Radio Linking Project (IRLP) allow for direct repeater linking. In addition, communications satellites called OSCARs have been launched with the specific purpose of operating as spaceborne amateur repeaters.
Echolink is a computer program that allows radio amateurs to communicate with one another using VoIP technology on the internet for at least part of the path between them.
The program allows reliable worldwide connections to be made between radio amateurs, greatly enhancing Amateur Radio's communications capabilities. In essence it is the same as other VoIP applications but with the unique addition of the ability to link to an amateur radio station's transceiver.
Updated 13 June, 2010 21:35:06 GMT