The Amateur Internet Remote Group (AIRg) is a group of amateur radio operators that use the internet to link local remote base stations. Stations are located in Conway, Russellville and Arkadelphia, Arkansas with Channel Islands Harbor in California.
The basic setup of each node is a computer (Windows in all cases here) running voip server software Ventrilo as shown in the node W5CND. A VHF, UHF or both radio and antenna. Audio coming into the receiver is fed into the mic input of the computer and audio going out first goes into a VOX unit that provides keying of the radio whenever audio is present and then audio along with push-to-talk is fed to the radio.
In the case of W5CND, HF operation on all amateur frequencies within 3 – 30 mHz is available. As for of the network, any node on the same voip channel will hear and be able to talk through that radio.
WD5B Node in Channel Islands consist of a remote RF node which also interfaces into a UHF repeater providing coverage around Oxnard and Ventura, California. WD5B also operates a VHF repeater in the area with better coverage. The VHF repeater has a remote link that can be brought up and inteface the VHF repeater into the AIRg network.
The main part of the network is the voice ip server (voip) which handles mixing each node’s audio and sending to all the other nodes. So, when there is a transmission from K5JU, the audio goes to the server and is distributed to all the other nodes in the same “room” for transmission. Users can switch between channels provide a link between only those stations.
System requirements are a fast computer with audio card to process the audio quickly, VOX interface box like SignaLink and an amateur radio. Oh, yes, you have to be licensed ham to do this.
We have gone with Ventrilo rather than Echolink, IRLP, Skype, etc. for several reason. One, Ventrilo will automaticly reconnect should the internet drop briefly or over a period of time. Ventrilo allows FULL duplex audio which means you can interupt a repeater or HF QSO even though audio on receive in coming through. And last and very important — Ventrilo has provide EXCELLANT audio quality. There is a delay of about 1 – 2 seconds in the distribution. Control of the system is by remote desktop software using both LogMeIn and VNC. Both are free and allow station control of each node both locally and remotely.
Look at Ventrilo or similiar services for VOIP, LogMeIn or VNC for remote desktop.
the attachments to this page:
aig_overview1
ventrilo01
wd5b
w5cnd
aig_overview
