On VHF, UHF and SHF repeaters are used, they have no importance or value on HF!
The idea of a repeater is to place it as high on a hill or tower as possible, allowing mobile and handheld QSO’s greater range and flexibility. This means that when a rig goes down a hill the signal hopefully shouldn’t drop out. Radio Amateurs are not the only users of repeaters, but ours are amateur radio dedicated. Other repeaters are operated by the Police/Fire and ambulance service & other Prime User Services, and in Some countries UHF CBers
A repeater accepts an RF input on one frequency and reproduces it on another (called shift) Many repeaters have One or more receive antenna’s and one or more transmit antenna’s. Whilst some radio’s have an inbuilt repeater option (often for crossband repeater use) these are not suitable really for the heavy duty cycle of permanent repeaters.
Many if not all of the UK based repeaters have a dedicated receiver and a dedicated transmitter these systems require duplexers with very high rejection levels so as to not cross contaminate the band in use.
Some of the new repeaters offer the following features
- Digital messaging services
- Digital Imaging services
- Internet linking*
Internet linking comes via several protocols, not all repeaters offer all services if in fact any.
- Echolink (all radios can handle this)
- WIRES (Yaesu technology)
- FUSION (Yaeus technology)
- D-STAR (Icom Technology)
Repeater Channel Allocations.
These refer only to FM repeaters Not SSTV
Access to a repeater is by CTCSS Tone each area uses a different tone, so you don’t swap repeaters by accident,