README.WWN SUGGESTED USE OF APRS IN THE WATERWAY NET APRS is the perfect tool for passing informal traffic to an from boats and for tracking boats underway. APRS was designed by a person with 20 years NAVY experience with tactical radar and data displays and ship-to-ship data networks on HF. APRS was designed to operate continuously in the background and provide connectivity between widely dispersed stations. It will provide position and status reporting for all units underway, in near real-time. I say near-real-time, because APRS should not be considered a mechanism for intense keyboard to keyboard conversations; but is ideal for exchanging one- liners over an extended time frame without having to contend with the problems of maintaining a CONNECTION. My experience in using APRS on the Naval Academy boats on summer cruise, is that with boats transmitting their positions and status once every 15 minutes, there is over a 90% chance that every boat will be seen at least once every 4 hours. PROPOGATION STATISTICS: A secondary benefit of the redundant beacons is that APRS operates like a poor-man's chirp-sounder. Since APRS keeps statistics on the number of packets heard from each station over the last 24 hours, this display can be used to verify HF connectivity between stations throughout the day. It's like a free radio check every 15 minutes everywhere! After watching APRS statistics for just a day, or so, the daily variations in propogation conditions to all stations is visible at a glance. Further improvements in connectivity is possible by changing frequency bands during the solar day. By saving statistics on each band in a different file, the APRS user can use this data to optimize his connectivity at any time of day or location. WATERWAY NET OPERATION: There is already a national APRS position reporting network operating on 7.085 and 10.151 LSB. (Tune 510 Hz higher if you are operating an AEA PK-232) All boaters and Recreational Vehicles are welcome! To see the locations of all stations on the net, tune your TNC to the exact frequency and monitor for at least 15 minutes. When you first activate APRS, it will send out a query to all stations on the network for their positions. If you are not properly tuned in when this query goes out, most stations might miss it. For this reason, APRS has the QUERY command so that you can manually initiate this ALL-NET APRS Query. After receipt of a Query, all stations will set a 2 minute random timer, and will respond sometime in the next four minutes. So be patient.. Even without a Query, all stations will transmit their positions once every 15 minutes... POSITION REPORTING: Their are several ways to report your position into the APRS network. First, run APRS and both your position and status will be reported automatically. Additionally, your station can send and receive messages to and from other stations on the net. If you turn off your PC computer, APRS places your position report in your TNC BeaconText so that your TNC will continue to report your last known position once every 15 minutes or so. This Beacon only contains your Position and words to indicate that your APRS program is not running. If you want your TNC to automatically report your position AND some meaningful status information, you can enter your LAT/LONG and additional comments manually into your TNC BText before Quitting APRS. GPS/LORAN AUTOMATIC REPORTING: With the optional APRS $9 interface routines, APRS can report your real-time position automatically. Simply connnect your navigation device NMEA-0183 output to your second PC COMM port. APRS will insert the NMEA position, course and speed automatically into your APRS position report. You can also do this without APRS and a laptop, by using the PACCOM TNC version 3.2 ROM in an HF compatible TNC. This TNC can be wired directly to a GPS device and set to send out your position on a set periodicity. OBJECT REPORTING: Since ANY APRS station can report the position of any other objects, your position can be automatically transmitted into the APRS network by ANY other station. Simply make a manual report to a friend or other waterway net member running APRS. He can put you on his map so everyone in the net will see you. Give your LAT/LONG, course and speed. You can also include about 28 characters (36 without Cse/Spd) of additional comments as desired. This is a good place to report your Estimated-Time-of-Arrival, etc. All APRS position reports are time stamped, so that there is no confusion as to when a report was valid. DEAD RECKONING: APRS automatically dead reckons all position reports. This causes all stations to see the most realistic positional display. All stations that are dead reckoned show up in light blue color and have an anchor line back to their last actual reported position. To defeat dead reckoning and display all stations at their last reported positions, simply use the CONTROLS-DR command to toggle off dead reckoning. When moving the cursor to select stations on the map display be sure to select the actual position, not the dead reckoned position. TRACK HISTORIES: APRS automatically saves all track histories to disk. To reduce redundant data, APRS normally filters out all positions from the same station that are within 80 yards of each other. This accounts for the random- ness of the Selective Availability. This filter can be turned off, so that all positions (that are not exact duplicates) will be saved. Fixed stations will only be saved once per track history file. These track histories can be replayed at any time, either from memory or from file. WEATHER REPORTING: All stations on the net can be apprised of unusual weather conditions by any station placing a weather symbol on the map. Just like stations, weather symbols will be dead reckoned between reports. In this way APRS is ideal for reporting the movements of hurricanes and tropical storms. There are over a dozen different weather symbols for this type of weather reporting. Secondly, APRS has a $9 optional interface routine for automatically reporting the wind speed, direction, temperature and rainfall from the ULTIMETER-II home weather station. All stations with this interface show up on the maps as a large blue DOT with a line indicating the wind direction and speed. Their position report also includes the temperature and the rainfall. Similarly, any station can select to use the Weather station symbol for his station, and can manually enter his wind speed and direction for display on the net. WATERWAY NET OPERATIONS: It is recommended that all Waterway Net participants that are HF packet capable begin reporting thier positions on the HF APRS nets. No changes to the existing voice net on 7068 are required! Since APRS will be operating continuously, 24 hours a day, it will provide a reliable and continuous background reporting of most stations. This will free up the voice net for passing of more voice traffic, and for position reports from non packet stations. One APRS station should volunteer daily to uplink the voice position reports into the network from his display by placing them on his screen as OBJECTS. Once these reports are being uplinked into the APRS net, any other APRS station can assume reporting responsibility for that OBJECT (station) simply by uplinking a later report. If the original station uplinking an OBJECT hears a later report, it will update its screen with the new report and will no longer report on that OBJECT since another station has taken reporting responsibility for that OBJECT. This enables stations to pass off APRS reporting responsibilities and keeps the network from being dependent on specific full time stations. WATERWAY NET MESSAGE TRAFFIC: All APRS stations are able to post a one-line braodcast message (BEACON) to all stations on the net. This can be used to alert all stations or make general announcements. Secondly, all APRS stations can send short message lines to any other APRS station on the APRS net. These messages lines are ACKed line by line for assured delivery. These short messages can be used throughout the day for making schedules for voice contacts on 7268 without the stations having to listen to the HF frequency all day. Since APRS does not use a CONNECTED packet protocol, these short message lines can be used all day long without the problems of timing out. After HF voice operations, stations that are packet equipped can just turn the volume down and park the HF rig on the APRS frequency instead of turning it off. This will keep them fully informed and reported without any additional effort. APRS NET FREQUENCIES: Since most boaters are using a back-stay or other non-resonant antenna with an antenna tuner, they have no problems operating the non-traditional WARC bands. For this reason, and to avoid all the QRM on 40 meters, I recommend that 10.151 LSB be the primary frequency for the WaterWay Net position reports. YES, THIS IS IN THE BAND! Operating LSB with 1700 HZ tones makes your radiated enegy centered at 10151 - 1.7 KHz or 700 Hz inside the band edge. The radiated energy of an HF packet signal is down by the required 40dB at the band edge. Because most HF packeteers have not done this math, you will find the frequency clean with no other packet QRM. If you still are not convinced, just tune to 10.147.6 and operate USB. It is the same frequency! We always speak of 10.151 LSB, however, since the convention on packet is to always refer to the LSB convention. (AEA TNC's will tune 510 Hz higher and lower respectively since they use tones centered at 2210 Hz). OTHER BANDS: An APRS reporting frequency should also be established on each of the higher bands as well. I have not done this, because both of my HF rigs are dedicated full time to 7085 and 10151. I would encourage distant travelers to stake out additional APRS frequencies on 18 and 24 meters. A good 20 m frequency is 14.100. YES THIS IS THE INTERNATIONAL CW BEACON FREQ, BUT IN LSB MODE, your tones are actually 1.7 KHz lower! THIS CAUSES NO PROBLEMS TO THE CW OPERATORS! (and takes advantage of the ignorance of many HF packet ops) This 20 m freq is for just playing around. New users could plop there and experiemnt with all the features of APRS without clogging up the RV and Boaters net on 10.151! NAVAL ACADEMY APRS NET: During summers only, the Academy operates an APRS net on 3 Navy HF frequencies for tracking its 20+ boats on summer cruises. Serious HF APRS shoreside stations might be useful for assisting the Academy in passing traffic. If you are interested, please contact WB4APR. APRS is also used by the Afloat MARS net for reporting the positions of all stateside MARS stations on frequency for passing phone patch traffic. The ships, of course, do not report their positions for security reasons, but using APRS to show the ships who is listening stateside has proved to be an excellent APRS application. For more information on the Navy MARS APRS afloat net, contact N1BFQ in New Hampshire.