Transcript Introduction to APRS

Introduction to APRS
Ken Adkisson, WB4FAY
www.wb4fay.com
[email protected]
Topics to be covered
What is APRS?
 Why do I want APRS?
 How do I view APRS?
 OK, now how do I go mobile?
 Current software
 The internet piece of the puzzle
 Upcoming goodies
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What is APRS
 Automatic
 Position
 Reporting
 System
 By Bob Bruninga, WB4APR
 Brief history
History of APRS
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Initial use as we know it in 1990 to track
boats during summer cruises. The
following flavors followed.
MacAPRS
WinAPRS
APRS+
pocketAPRS
PerlAPRS
XAPRS
www.findu.com
Why do I want APRS?
For Starters….
 Ok, Joe Ham tells me he has a bike
rider down but has no clue were he
is.
 Or, Joe Ham has hail coming down
and still has no clue were he is.
 Joe Ham is part of a disaster
evaluation team.
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How do I view APRS?
Basic setup for a fixed station
Home Stations
This can be:
EOC
NET Control or Home
TNC
PC with maps
Radio on local frequency
Software
There are many flavors to APRS
 DOS APRS
 WinAPRS and APRS+SA
 XAPRS for Linux
 pocket APRS (Palm Pilot)
 APRSdigi and Uidigi (digi software)
 PerlAPRS
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OK, now how do I go mobile?
TNC route
 Mic-E route
 Soundcard as TNC
 GPS receiver
 Do I have/want to use a laptop ?
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– Use Sound Card for TNC ?
Mobile Equipment
TNC Verses Mic-E
TNC route requires a separate radio
 Mic-E can go in-between radio and
microphone
 Either route can be run on separate
radio
 Either route is referred to as a
“TRACKER”
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Definitions
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A tracker is a mobile station
Posits are position reports
UI Frames are frames that do not employ
error correction techniques, entirely that
is.
Digipeaters are stations that act as a
simplex repeater except in a digital format
IGATES are stations that feed data to and
from the internet
Definitions

GATES are stations that take the HF APRS
data and retransmits them on VHF and
possible the internet.
 IGATES are stations that take the APRS
data and retransmits it between an RF
channel and the internet.
 APRServers are stations that IGATES send
data to and redistribute them to the
IGATEs
How does it work, basically?
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A tracker or fixed stations sends out a UI
frame that has lat/long and possibly other
data (e.g. altitude, course, speed, wx info,
etc.)
 If the packet burst passes the checksum,
the info is then displayed on the screen.
 If the checksum fails, the packet is lost.
This is not a big deal since the posit will
be transmitted again soon.
The Next Level
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IGATES, why would I want to do this?
 IGATES provide a feed to the net so
everyone can see what is going on and
allows for messaging on a world level
 Balloons, mobile stations, weather events
you want to track, using automated
watch/warning data to transmit in your
area.
What else can I do with APRS
Connect your weather station
 DF abilities
 track vehicles (balloons, trucks,
space vehicles, hurricanes)
 messages
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Guy Story:
W8XF balloon launch
on 8-3-97. The X
indicates max
altitude achieved.
Digipeater does and don’ts
Other station tips
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What is my tnc deviation?
The target is 3 kHz deviation
Greatly improves channel throughput.
Go to http://www.febo.com/packet/layerone/index.html for more data.
Open squelch??????
Hidden and deaf transmitters