Presentation is loading. Please wait.

Presentation is loading. Please wait.


Similar presentations

Presentation on theme: "BARC – CC ARES –"— Presentation transcript:



3 Northern Utah APRS Network

4 Why We Are Here APRS is a powerful tool for emergency management Readiness requires skilled reserve of Hams

5 What is APRS Automatic Packet Reporting System Packet communication protocol for sharing live data on a network in real time Real time tactical communications and display system for emergencies and public service applications (APRS Spec)

6 APRS Features Maps Messaging Objects Bulletins and announcements Weather station reporting DX Cluster reporting Internet access Telemetry Voice Alert

7 History Invented by Bob Bruninga, WB4APR in 1992 The Automatic Packet Reporting Sys- tem was designed to support rapid, reliable exchange of information for local, tactical real-time information, events or nets.

8 History APRS for DOS was the first program MacAPRS & WinAPRS 1994 by Sproule brothers UI-View—best & most popular Many other APRS apps since – runs on Windows 3.x, NT and XP, Mac, Linux, iPhone, Android and DOS GPS adjunct came afterwards

9 Uses Passive Fun –Watch the display of many stations –Watch the ISS or PCsat fly by –Watch emergencies in action Tracking –Find your buddies –Track your teenager, wife –Balloons, rockets and public service events –Meet hams spontaneously on the road

10 Uses Telemetry –Balloons and rockets Post bulletins, event notices and venues Send short messages Send email

11 More Uses Events –Track the parade Grand Marshal –Track the last marathoner or bike racer Emergencies –Search and rescue –Disaster information –EOC messaging (Single Line) –Track the fire chief

12 Still More Uses Weather monitoring –See wind speeds and temperatures in the area –Report wind damage –Track tornados

13 Weather monitoring Users can create and move objects such as hurricanes and funnel clouds. The objects can be transmitted through the APRS network to the NWS Objects could be used to transmit attributes not quantifiable as a number Collection of data Trending Weather Data Weather Alerts from NWS Superimposed RADAR

14 Theory Assumptions Packet radio Digipeaters APRS Protocol Frequencies GPS

15 Assumptions Radios Antennas PC Skills

16 How does APRS Work? Some details…

17 Packet Radio History –AX.25 protocol was approved by ARRL in 1984 –Came from X.25 protocol (the A is for Amateur) –Primary difference from X.25 is allowance for call signs and for unconnected packets

18 Packet Radio Packets –Strings of data bytes called frames –3 kinds of frames in ordinary packet Information (I frame) Supervisory (S frame) Unnumbered (U frame) –6 kinds of U frames, one is Unnumbered Information frame –UI frames are used for transmitting data in an unconnected mode

19 Packet Radio In packet radio, qso’s are always between ‘connected’ stations Several qso’s can take place simultaneously on the same frequency Packet qso’s may be digipeated but by specific stations

20 How is APRS different from Packet Radio? Communication is ‘one to many’ Uses generic digipeating with well- known aliases Supports intelligent digipeating to reduce network flooding Uses UI frames for messaging, bulletins and announcements Provides maps and other features

21 How APRS uses Packets Uses the same AX.25 protocol but only a part of it Uses Unnumbered Information (UI) frames exclusively Always runs in connectionless mode

22 How APRS uses Packets Frames are transmitted without expecting any response Reception is not guaranteed Messages work same way but use an ‘ack’ technique

23 The UI Packet

24 Destination Address From the APRS spec…

25 Destination Address The adr ‘SPCL’ is to be used for special events. APRS s/w should provide for only showing stations with this adr (but it doesn’t). Usually just shows the software version. WinAPRS v2.6.1 sets this to APW261

26 Destination Address




30 May also contain –MIC-E encoded data –Other unique encoded data No reason to change this since s/w can’t cope

31 Source Address My station call sign

32 An Intervening Word about Digipeaters Why do we need them? –Increase coverage Digipeater versus repeater –Voice repeaters operate in duplex mode –Digipeaters operate in simplex mode –Digipeaters use store and forward technique

33 Digipeaters Wide area digipeaters –In this area are usually on a tower –Have good antennas and high power –Operate automatically –Operate all the time –Have Battery Backup

34 Digipeaters Fill-In digipeater –Usually somebody’s home station –Should be able to communicate with a WIDE station –Purpose is to help low powered stations get to the WIDE

35 Digipeaters WIDE –Examples: KF7VJO-3 …or not –Examples: W7BOZ

36 Digipeaters


38 FIX #1: Phase out RELAY and WIDE Paths (also eliminate TRACE, TRACEn-N): The single biggest improvement in the USA was simply getting users to stop using the obsolete RELAY and WIDE paths. The obsolete RELAY and WIDE paths generated multiple dupes in the KPC-3 and PacComm and some other implementations because there is no dupe elimination for dupes heard from other digis.. These obsolete paths generated 3 to 5 times more load on the system than the comparable WIDEn-N path which has perfect dupe elimination algorithms. The fix was easy. Use WIDE1-1 in place of RELAY and WIDEn-N in place of WIDE.

39 FIX #2: Make WIDEn-N Traceable : The original WIDEn-N system was not traceable, making it impossible to do any network assessment or management.. The New-N Paradigm made WIDEn-N traceable!.. (By eliminating TRACEn-N, Sysops can now move WIDEn-N support from the UIFLOOD parameter to the UITRACE parameter.)

40 FIX #3: Use WIDEn-N everywhere. The New n-N Paradigm Solution: WIDEn-N is the most efficient APRS path, but it is vulnerable to out- of area QRM from user settings of large values of N.. Fortunately, under the New n-N Paradigm, existing digis now trap large-N abuse and greatly simplify user recommendations to simply one WIDEn-N path.. The New n-N Paradigm simplifies the APRS network to a few distinct digipeater types: WIDEn-N..- The basis of the New n-N Paradigm. They also support SSn-N for state nets (S overlay). WIDE1-1...- Fill-In digis (where required only). Set these fill-in digis MYALIAS to WIDE1-1. One-Hop.. - These digis force big-N packets to 1 hop in extreme density areas. (LA or Dayton for example) PacComm. - These old "T" digi ROMS can still be used locally for up to WIDE2-2 support (with P overlay)

41 Fix #6, Proportional Pathing for DIGI beacons! One of the biggest loads on the network prior to this New-N Paradigm was simply the flooding in all directions at all distances of the individual DIGI beacons. Many digis were sending out their beacon to 4 and 5 hops in all directions every 10 to 30 minutes. There is no need for this spam.. So part of the New-N paradigm was to come up with the Proportional Pathing algorithm that kept the information update rate at 10 minutes in the immediate direct range of the digi so that passing travelers would be informed, but then the rate was much less for more hops to cut overall load on the network and out-of-area spam.

42 Back to the UI Packet -- Digipeater Addresses Also known as the ‘unproto path’ Up to 9 addresses Specific or generic aliases Specified in s/w configuration or in the UNPROTO command: APRS V WIDE1-1, WIDE2-1 Represents the route you want your packet to follow

43 Digipeater Addresses Rules of thumb –Don’t use RELAY –If you can hit a wide, then include it as the first digi in the string –For maximum range, add WIDE2-2 or WIDE3-3 after a specific DIGI Examples: APRS V KF7VJO-3, WIDE2-2 APRS v WIDE1-1, WIDE2-2 APRS V WIDE3-3 Anything MORE than 3 should be avoided!

44 Digipeater Addresses –You can be really specific about the path Example: APRS V KF7VJO-3, REDSPR, BLKMTN would route you up to Star Valley, nowhere else

45 Types of Data There are ten main types of APRS Data: –Position –Direction Finding –Objects and Items –Weather –Telemetry –Messages, Bulletins and Announcements –Queries –Responses –Status –Other

46 Data Example Position data

47 Data Extension Example PHG extension refers to power, height and gain (also directivity) –Height is above ‘average local terrain’ Form is ‘PHGphgd’

48 Frequencies VHF 144.39 –1200 baud HF 10.15151 LSB –300 baud Satellite –ISS Downlink 145.800, uplink 145.990 –PCsat simplex 145.828 –1200 baud

49 Getting on the Air with APRS – What to Buy/Scrounge Details…

50 Hardware Home station requirements –2 meter radio and antenna –Desktop computer –TNC or soundcard/interface Mobile station requirements –2 meter radio and antenna –Variables

51 Hardware Mobile variables – Track & View –GPS –Laptop –TNC

52 Hardware Mobile variables – Mobile Tracking –GPS –Tiny Track, or Tracking TNC

53 Hardware Mobile variables – Portable tracking –GPS –No computer –Tracker interface device –Power source for portability

54 Hardware Kantronics KPC-3+ –Supports single PC Serial Port Tracker –Supports UI Flood Protocol –Current Version is 9.0 –Simple Mobile Operation –Cost $189

55 Hardware Kantronics KPC-3 –Good for Home use –Version 8.2 Supports UI Flood Protocol –Average cost used: $80

56 Hardware KPC-2, KAM, MFJ, others –Good for Home use –Low cost –Check for deals

57 Hardware Kenwood Mobiles – TM-D700, TM-D710, TM- D710G AV Map

58 Hardware Yaesu Mobiles AV Map FTM-350AR No longer in production

59 Hardware –A self-contained tracking/telemetry module Tiny Trak 4 Kit ($65) Already built ($75) Tiny Trak 3Plus kit ($33) Already built ($42) –See

60 Hardware Computers –Running with a TNC doesn’t require a fast computer or recent O/S A slow machine means your maps will refresh very slo-o-o-oly –As with all apps, more memory is better

61 Hardware TNCs –Any TNC will do when a computer is attached. –Old style TNCs may not be GPS aware, but they work for base stations

62 Hardware Cables –Sources Packet http://packetradio.com MFJ http://www.mfjenterprises.com

63 Hardware –TNC cables Computer serial port to TNC –Unique to your TNC TNC to radio mike connector –Unique to your TNC and radio

64 Hardware Consideration for GPS with TNC –2 serial ports are needed (Unless KPC3+) –If only 1 serial port is available, can use a “Port sharing” device

65 Hardware GPS Receivers –Must have PC interface port –Must output NMEA messages on the PC port –Good to have an external antenna for the GPS –RS-232 or TTL

66 Software WinAPRS –Pros Everybody knows about it Free maps Can use high quality Precision Maps Unregistered version has full functionality

67 Software –Cons Help function is bad Not totally stable Not everything works Maps aren’t so good Expensive to register Somewhat limited in scope

68 Software APRS+SA –Pros Comprehensive functionality High quality Street Atlas maps

69 Software –Cons No (I said no) help Hard to manipulate maps Confusing Only works with Street Atlas Have to register to use AGWPE Expensive to register

70 Software UIView –Pros 16 bit version is free, 32 bit version is free too but they request a donation. Quality coding Extensive help files Any GIF or bitmap file can be a map Works with Street Atlas and others Detailed Street level Mapping with Precision Maps

71 Software –Cons Limited Individual Replay options Author has passed away and sotware no longer supported

72 Software Xastir –Pros Works on Linux Good map capability –Cons Not a Windows program

73 Software MacAPRS –Shares same code with WinAPRS

74 Software APRSICE/32 –Pros Follows WB4APR’s APRS spec very well Maps are available Connects to the internet –Cons Has to be connected to the internet to get maps Hard to configure. Especially to use on RF

75 Software My recommendation –Use UI-View with Precision Maps 8

76 Satellites ISS –Excellent signal PCsat –Built by Bruninga’s students at Annapolis Find the satellite’s position – rack/Spacecraft.html

77 Another way to view APRS Internet APRS.FI –http://aprs.fi –Great online tracking source. –Does dead reckoning FINDU – http://map.findu.com Struggling to find a free mapsource

78 Voice Alert Have you ever driven on an all day trip and never found anyone to talk to? Have you passed someone with antennas all over the roof of his car, yet, can't raise him at all? Have you tried to look through the Repeater Guide to help you find a local QSO repeater, but find the listing of 10,000 mostly silent repeaters daunting, especially while moving? Remember, statistically, one out of every 500 cars you pass is another ham! On some interstates, that is one every 10 minutes.

79 Voice Alert Now, imagine a HAM radio radar that automatically alerts you to other mobiles in simplex range, or a dual band radio with a permanent 3rd full-time nationwide Voice Alert CALL channel that is always on. Driving the interstates with such a radio would guarantee you a new LOCAL contact on average about every 10 minutes or so! Amazingly, such a radio does exist, in fact, two of them. Thousands of HAMs have them and most use them every day. But unfortunately, many of these owners, do not fully use the radio to its full potential on the open road and most of the rest of us are unaware of their amazing functionality. The radios, of course, are the Kenwood TH-D7A(g) Handheld the TM-D700/710 and the Yaesu FTM-350R APRS mobile radios. (And any other APRS radio with the TNC connected directly to the discriminator).

80 Voice Alert But in the year 2001 or so, we realized that EVERY single APRS mobile operator out there was driving around with a radio guaranteed to be ALWAYS listening on the same North American Continent wide channel, 144.39. The only problem was they all had the volume turned completely off (who wants to listen to a wall-to-wall packet channel while mobile?). Well, it only takes about a second's thought to realize that if we simply turned up the volume to normal level, and set CTCSS-100, then the speaker would still be ALWAYS QUIET, but if someone in simplex range did want to call us, then he could do so with PL-100 and we would always hear the call! Think of it as a 3rd radio in the car. Always on, Always listening for simplex calls, and yet completely silent at all other times. We called this great concept "Voice Alert".

81 Important Links NEKSUN APRS Tucson Amateur Packet Radio (TAPR) – http://www.tapr.org NWAPRS – http://www.nwaprs.org Bob Bruninga WB4APR’s site - http://www.aprs.org Tiny Trak - Web Tracking - Another Web Tracking - - Yet another Web Tracking - Open APRS Website - http://www.openaprs.net ARPRICE/32 - UI-View Web site - Balloon/Rocket tracker - Argent Data Tracker - WA8LMF Website - K9DCI APRS Beginner Guide - %20-%20K9DCI%20Ver%205-1.pdf %20-%20K9DCI%20Ver%205-1.pdf

82 Questions ??

Download ppt "BARC – CC ARES –"

Similar presentations

Ads by Google