2016 Update on APRS
What is APRS?
Its creator describes it as a “digital
communications information channel”
APRS stands for Automatic Packet
Position Reporting System.
Most often used as a “tracker” to show
the location of objects
Intended to show ham radio activity
APRS Fundamentals
TNC generates a “packet” of information and sends to
radio
Radio transmits the packet - usually on the standard
144.390 APRS frequency
Packet is often received and re-transmitted by digipeater
Packet is received by other APRS radios an decoded by
their TNC.
Packets received by “igate” transmit information to
internet
Locally
W5PFC-2 digi on the air
W5PFC digi currently off the air
K5ZRO digi replaced and updated
Local/small area digis
Statewide - many more on the air
Reduced Participation … until Fusion
Equipment
Upgraded equipment
from Kenwood
Yaesu's new Fusion
radios
Various dedicated
trackers
Argentdata TNC
Packet Path
(Historic Settings)
RELAY, WIDE
RELAY, WIDE, WIDE
Some older equipment still defaults
to these settings
Packet Path
(The New Paradigm)
WIDE1-1, WIDE2-1 (recommended for most
mobiles)
WIDE1-1, WIDE2-2 (recommended for
mobiles in rural areas)
WIDE2-1 (recommended for fixed stations)
For a good explanation of paths, see:
W8lmf.net//DigiPaths/
SSIDs
Initially associated with
station icon - no longer
the case
Now used as an
informal way of
indicating APRS
applications
Good discussion at:
www.aprs.org/aprs11/
ssids.txt
SSID
Recommendations
-0 primary station, usually fixed and
message capable
-1, -2, -3, -4 generic additional station,
fixed, mobile, digi
-5 Other networks such as dstar or
cellular
-6 special activities
SSIDs Continued
-7
HTs or other primary human portable
-8
Boats, RVs, or other secondary mobile
-9
Primary mobile, usually message
capable
-10
Internet, igate, echo link, etc
-11 balloon, aircraft, spacecraft, etc
More SSIDs
-12
One way trackers, etc
-13
Weather stations
-14
Truckers and other full time drivers
-15
Generic additional station, digi, etc
-A through -Z for dstar
Newer features
Voice alert
Serves as a
proximity radar
Brief voice contact
to move to a
different frequency
Newer radios do
this by turning
feature on
Setting up Voice Alert
On newer radios
turn feature on from menu
turn volume up
On older radios
set ctcss to 100hz
Turn volume up
Optional: set monitoring frequency
On non APRS radios
Set ctcss to 100hz
Limited functionality
Calling on Voice Alert
"(Your call) listening on voice alert"
"Voice alert, (your call) listening on
52"
Voice Alert
The Big NoNo
Do not use on base
station
Impact of Yaesu
System Fusion on APRS
Prior to Fusion, APRS was in decline
Fusion system has resulted in increased APRS
activity
Some local stations using Fusion radios for
APRS: KG5FSA, WM5A, K4FMH, WX5H, KF5DII,
W5PFR, KG5IIS
Some local Fusion repeaters on the air:
146.88, 443.500, 441.700, 444.900
Comparison of APRS
with Fusion GM
APRS works direct or through
digipeaters…..best through digipeaters
Fusion Group Monitor (GM), as best I
can tell, works best in simplex
APRS works independent of voice mode.
GM works only on voice side in Digital
Narrow (DN) mode
Fusion Group
Monitor Screen
Navigating to GM
Station
Newer features
AVRS
Automatic Voice Relay
System
Sometimes callers A-Star
Movement to interconnect
multiple platforms (dStar,
IRLP, echo link, APRS,
etc.)
For more info, see
http://www.aprs.org/
avrs.html
Some Resources
www.aprs.org
www.mcminnarc.com/aprs/
unproto.html
k3ars.org/smf2/index.php?
topic=1139.0
xastir.sourceforge.net/