Many dual-band transceivers offer a "cross-band repeater" function, useful for linking local portables with distant repeaters, or as a quickly deployable hill-top repeater.
Crossband repeat, for those unfamiliar, is a feature offered by some dualband mobile rigs, in which one side of the radio listens to a 70cm simplex frequency and retransmits what it hears on the input of a 2-meter repeater. Audio from the 2-meter repeater’s output is retransmitted on the 70cm simplex channel. That allows the user to walk around talking and listening to the 70cm simplex frequency which is connected to the repeater via the mobile radio.
So how is this used for ARES? Well simply put we basicly create a local repeater for members to access with their HT's in the field. As an example the EmComm trailer is set up at a location that is difficult for HT users to reach a repeater but by setting up a cross-band repeater in the trailer users are now able to access the repeater through the EmComm trailer. Some of the advantages for this would be:
-
HT users can now use less power and conserve battery life.
-
A more reliable signal into the repeater (5W vs. 50 - 100W depending on location)
-
A cross band repeater is far less expensive than a conventional repeater.
These are just a few of the advantages of this mode. If you would like to know more about this mode of operation in conjunction with ARES leave a comment. If we have enough people interested we will create program that covers this and include a demonstration.