Kenwood TH-D72A/E - Manual (Page 70)

7 APRS NETWORKS
62 CONTENTS TH-D72A/E
Since all of these transceivers can be used as backup emergency digipeaters anytime, anywhere,
someone that is unable to hit any digipeaters from their current location with either WIDEn-N or SSn-
N can always try TEMP1-1,WIDE2-2 to get out. Or, if all the digipeaters in an area are off-the-air, he
can actually try TEMP2-2 to get two mobile hops (or more) to a temporary destination. To further
benefit this alternate backup digipeating technique, some special battery-powered backup
digipeaters at high locations can also support this path in addition to WIDEn-N and SSn-N paths as a
full time backup to the existing system.
It is necessary to confront the issue of frequency congestion due to the spread of APRS systems in
order to efficiently transfer packet data (paradigm). TH-D72A/E supports the configurations of New-N
Paradigm, RELAY Paradigm and STATE/SECTION/REGION. Overall, this provides an efficient
mechanism for transferring packets.
Appropriate configuration is required in order to digipeat a packet path (relay route). New-N
Paradigm using WIDEn-N assigns an alias and a relay stage number for digipeaters. This system is
spreading worldwide.
For example, when you desire two hops, then you can configure “TOTAL HOPS: 2” and once
configured, you can verify that the packet path is configured to WIDE2-2. In the past years, when a
regional digipeater was wanted, RELAY was used but this is replaced by WIDE1-1. You can use
WIDE-1-1 simply by configuring On via menu selection Again, you can verify on the configuration
screen that “WIDE1-1 or WIDE2-1” was used for the relay route.
This is one of the digipeat types used in Europe. The old backwards compatible RELAY technique
was included for some areas that have still not updated to the universal New-N Paradigm using
traceable WIDEn-N. It allows the first hop to be via the RELAY path and then uses TRACEn-N for
subsequent hops. The USA is using the New-N Paradigm. But, Europe has not yet fully coalesced
into RELAY PARADIGM as of this writing.
7.5 Packet Path
7.5.1 New-N Paradigm
7.5.2 RELAY Paradigm