Kenwood TM-D710GE - Manual (Page 45)

06 APRS Networks
41
Servers
In the beginning, APRS networks consisted only of general packet transmissions through digital repeaters. To expand
network coverage much further, HF gateway stations that were interfaced with the VHF stations were added. This
arrangement evolved still further when it became common for personal computers to be connected with the Internet.
Internet gateways provided another way to expand APRS coverage. APRServe, developed by Mr. Steve Dimse, K4HG,
allows information that is gathered from the Internet to be transferred to client computers. The worldwide APRS network
was completed. The service is called APRS IS (APRS Internet Service).
At present, there are several basic servers that are called Core servers. Approximately 40 local servers, called Tier
2 servers, are located worldwide in each participating country and work under the Core servers. Later, Pete Loveall,
AE5PL developed javAPRSSrvr to establish a Tier‑2 distribution system to better handle regional APRS‑IS feeds. The
Internet part of the APRS system is called APRS‑IS (APRS‑Internet Service).
IGate
There are basically two ways to use APRS-IS effectively when operating APRS: a client personal computer connected
directly to Core/ Tier 2 servers, and using amateur radio with IGate (Internet gateway).
For client use, a callsign is required, but amateur radio equipment is not necessary. You simply install APRS software on
a personal computer, configure the necessary station information and connect to an APRS server via the Internet. With
this arrangement, you can enjoy the basic features of APRS such as transmitting your own station position, exchanging
messages and dispatch or receipt of weather information.
Using TM‑D710 or RC‑D710, you can transmit your own packet signals via amateur radio and use APRS‑IS to access
IGate. IGate acts as a two‑way interface between the Internet and amateur radio packet signals. The IGate function
is obtained through various releases of APRS software and IGate is commonly available as a result of many volunteer
amateur radio operators. IGate connects directly to Core servers and Tier 2 servers. Information received by amateur
radio packet transmissions is transferred to the servers, and server information can be passed via packet radio
transmissions back to amateur radio operators.
New IGate stations in areas where IGate access is already available are added as necessary as traffic warrants. Traffic
from IGate to amateur radio stations increases air traffic which can undesirably overload frequencies. Therefore, you
must be familiar with operational configurations. Various filtering functions exist so you should be knowledgeable about
your local existing IGate station. It is best to minimize traffic as much as possible. In the case of packet messaging,
bidirectional data transfers are used.
To use TM-D710 or RC-D710 efficiently at a fixed station includes configuring the callsign and the packet path to your
local IGate station. In cases of mobile stations, you can similarly initially configure the packet path, but it is good to
follow local rules of each new area where you may operate.