Automatic Voice Relay System: AVRS

The major initiative that has been driving just about everything new in APRS since the 2001 time-frame has been making sure that APRS can support the signalling and information system needed so that hams can TEXT or VOICE to any other ham anywhere at any time using any device and any VOIP system knowing only a callsign.

The TEXT version of Universal hamradio Text Messaging is covered on my www.aprs.org/aprs-messaging.html and a Sep 09 QST article.

But the VOICE version, called Automatic Voice Relay System is on: www.aprs.org/avrs.html

When I was at the HRO Grand-Reopening in Atlanta I got to talk with some D-STAR folks, and D-STAR is another part of this global AVRS initiative. D-Star can already connect voice using call-to-call addressing. Echolink, IRLP and WIRES can do it also using APRS as the callsign, and node locator.

We have been working on this for now a decade and are making progress. In addition to D-star, the other key elements have been:

1) Encouraging all DIGI owners to have local FREQ objects
2) This includes Echolink, IRLP and WIRES objects
3) The auto QSY TUNE button on the TM-D710 radio
4) The auto QSY button on the Yaesu FTM-350 radio
5) The auto QSY/TUNE button on the TH-D72 HT
6) Client implementation of ITEM-IN-MESSAGE (APRSISCE)
7) APRS radio receipt and display of ITEM-IN-MESSAGE

The last two allows the AVRS engine that sets up the voice link to analog users to send back a FREQUENCY OBJECT to the CALLER and the CALLEE showing them their local IRLP, Echolink or VOIP node to use to complete the call. Eventually, when future APRS radio versions receive this QSY packet, they will automatically go to the VOICE channel to complete the voice call which was initiated on APRS by simply sending a voice-link-request message to "AVRS" containing the CALLEE callsign.

There are still lots more little interfaces and gateways that are needed to conect everything together. For example, a D-STAR user could establish or receive an Echolink or IRLP voice link if someone simply wrote the gateway interface. APRS then extends this to the mobile analog user via the APRS object and FREQ QSY system to get him on the right RF frequency.

Anyway, after 9 years, the hardware and mechanisms are now in place. We just have to get all the smart programmers and egos in the same room and get them cross connected.

Bob, WB4APR

Our thanks to Darren, G7LWT for relaying the above information from the APRS SIG

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