Installing APRS
Installing APRSdos version
Although it might seem confusing, installing APRS dos is very easily.
The following instructions will allow you to install APRSdos with a simple step-by-step install.
- Make a directory on your hard drive called APRS
- Copy the downloaded APRSxxx.ZIP file to this newly created directory (i.e. C:\APRS)
- Unzip the program with PKUNZIP. If you don't have PKUNZIP, look for it on a shareware site like http://www.pkware.com. To unzip the program, type this:
PKUNZIP -dn APRSxxx.zip
It is important that you leave the -dn as lower case. Upper case DN means different things to PKUNZIP program.
- Do a DIRectory command and look for the APRSxxx.EXE program. This is what you will type to invoke APRSdos. Installing APRSmax is done the same way.
You are now ready to start APRS and give it some data. Before you do, there are a few things you should know.
- APRSdos only runs on a regular TNC. Sorry - no baycom modems.
- APRSdos doesn't use KISS mode in TNCS at this time.
- APRSdos runs on a little as an XT with 640K base memory, and doesn't use
any extended memory to run. A minimum of CGA is required and some users
have reported that they could get a monochrome monitor to run with APRS if they used a support program called SIMCGA.COM first before invoking APRS.
- Make sure you know what serial port and baud rate your modem is set to. Make sure its connected and turned on. If your unsure what baud rate the tnc is using, check the switches or ABAUD setting using your favorite packet program. APRS runs best at 9600 or 4800 baud.
- If you have a Kantronics TNC, make sure the tnc isn't in HOST or NEWUSER mode. This really causes a lot of problems for Kantronics tnc owners at first.
- Find out what your Latitude and Longitude is. Don't worry, as there are several ways to find out as you will see below. A quick discussion on this is available here.
- Figure out how many hours behind UTC your location is. This will be a negative number if your in the USA (-5 to -8 PST) If your location is currently in a "Daylight savings" mode, the number will be one hour less (-7 hours in California in the spring and summer months, vs. -8 in the winter time)
Running the program
- Invoke the program with the name you saw in the directory above. (APRSxxx.exe)
- Enter your callsign. If you want to have a SSID (-1 through -15) enter it with your callsign (i.e. WA6YLB-12)
- The program will then ask you if your going to use Dual ports [ two serial ports active - such as TNC on one port, GPS or Wx on another ], Single port [just one serial port active - perhaps just a TNC ], or Modem remote [ to connect to internet with a RS232 Telnet connection ]. Typically choose S for single port.
- The next question will be which COMM port the tnc is on. Your answer should be 1 or 2 with the 1 in brackets a default answer if you were just to hit the ENTER key with out any number entered. Comm ports 3 and 4 are not supported by the program compiler.
- Enter the baud rate you communicate to the tnc. 4800 is a supplied default. Enter all four digits to
have a value other than 4800 baud. Then hit ENTER.
- Select which band you want to operate on. This choice selects different options inside APRS. Default of VHF is made in the brackets.
- Choose which kind of TNC MFG you have. This is a single letter choice, and when the keystroke is entered, it will move to the next question without hitting the ENTER key. If you have a PK88, don't choose AEA. Choose neither.
- If you happened to choose one of the MFGs such as Kantronics, it will ask you to choose between models.
answer Neither if the tnc isn't exactly listed there.
- If you had chosen Dual ports above, you would be asked at this point to declare what type of device is on the second serial port. It then will ask you questions about the second item, such as port #, baud rate, values for units etc.
- The program will ask you to declare what the clock in your PC is set to. Either Z for Zulu (UTC) or L for local time zone.
- Enter the offset between Zulu (UTC) and the timezone you're in. Use -8 for California when not in
daylight savings mode. (-7 if in Daylight savings mode)
- The program then asks if your area is using Daylight Savings time. I usually just enter the real offset from UTC above, and answer N to this question.
- Next, the program will ask you to read about APRStel.sys, and then ask you to hit N to not see it again.
At this time, a map of the USA will be drawn. You will notice that in the very center of the screen is a yellow circle. This is referred to as the "cursor". You can move the cursor around with either
your MOUSE or the arrow keys on the keyboard. If your MOUSE doesn't move the cursor, load a DOS mouse driver before invoking APRS. The PgUp and PgDn keys are used to zoom out and zoom in on the map. Try moving the cursor to where you live. You should have your radio and tnc turned on and be monitoring the local APRS channel (144.390 MHz in USA and Canada). By this time, you should have heard your PC beep a few times, and may have noticed that your radio is transmitting every once in a while.
Inputting your POSITION
If you were unable to obtain your latitude and longitude, move the cursor to the place on the map you believe you're at. Zoom in several times to properly place yourself. When you move the cursor, hit the HOME key to re-center the map where the cursor IS. Then zoom in with PgDn key. You will notice that in the top left corner of your screen a position box holds the current lat./long of where the cursor is. Use these numbers "exactly" as shown in this next step. If you were able to find out your latitude by using a GPS / TOPO map / Etakguide, use those numbers instead.
- Hit I M P as three keystrokes to Input - My - Position.
- The first question asks you to enter your Latitude. Enter it in the format shown in the square brackets. If you found your position with the cursor, then the value in the square brackets is correct, and you then just hit ENTER. You should fill in all 6 digits for your Latitude though. Format is DDMM.MMn or DDMM.MMs
- Enter the longitude in the same way. Format is like Latitude, but you need three degree values - DDDMM.MMw or DDDMM.MMe
- APRS wants to know what kind of symbol you want to be on maps. Most people choose Q for
QTH.
- A list of icons for Q is now shown. Choose 1 or 2. Don't choose 3 for an quake.
- APRS wants to know what direction your station is moving (like a boat or balloon). The default of 000 is correct for most users. Hit ENTER to choose 000.
- Same for the speed. Hit the Enter key to choose 000 mph. Most homes don't move that fast!
- APRS wants you to input something for a beacon. Some users put their EMAIL address in at this
point. You could input your name and city in here. This could be helpful if you're really not sure if you got
the right location on the map. Experienced APRS users will be able to "find" you if they know your city and your latitude and longitude numbers are wrong.
- APRS wants to know "as of what time" this information is correct. Most users hit S for the same time
as the clock is in the PC.
- New position correct - answer Y here, and it will send out a position report to the active net. A "n" here will cancel all this inputting (like an escape).
Your station ICON will appear at the location on the map. Move over to it, and zoom in,if your not
already there.
Adding a path
APRSdos has a default digipeater path of RELAY,WIDE. If your area contains an active APRS network of Digipeaters, your signals
should be digipeated right away. If you see the message " APRS did not see a DIGIpeat of your last packet...", this means that APRS tried to transmit via a digipeater, and didn't see your own packet being repeated out over the air. Usually your own outgoing packet is always seen via a digipeater when a digipeater path is declared, unless it was destroyed by another station transmitting at the same time or simply never made it to the digipeater. Another reason for this message, is one of poor path or bad conditions, such as too far from the digipeater, or distorted signals to or from the digipeater. It's really a tool to help you understand how well your signal is getting out. If you see this message on every transmission, then your range is quite small (you may have a problem).
After monitoring the network for a while to see what digipeaters are availible, use the U command in APRSdos to set up an UNPROTO path. The VIA and "TO:" address need not be inputted.
When you hit the U key, you will see what the path in APRSdos is currently set as. This whole area of paths needs some explaining.
While APRS digis will respond to "Alias" callsigns of WIDE and RELAY etc, using a whole string of ALIAS callsigns on a regular basis isn't desirable. In my opinion, its best to "learn" which digi are the best (closest or best signal to/from your location) for the path you want to use. After placing its callsign as the first digi in the path, then you may want to use WIDE after this. RELAY is used mainly by mobiles, which need all the help they can get. RELAY should only be used as a "FIRST" callsign in the digi path, mainly for mobiles. Every APRS station responds to RELAY by default. Adding RELAY to your path should be done with caution. Watch the network of DIGIS grow on your screen. If you had a RELAY after a WIDE, then every station that could hear the WIDE aliased DIGI will digipeat your packet. This adds a great deal of duplicate packets to the network, and is frowned upon by fellow APRS'ers.
Once you get a feel for where digis are, then you should consider using actual callsigns of the DIGIPEATERS in your path.
More information on the use of APRS will be forth coming. Stay tuned to this web page.
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created 12/26/97; last date of modification 12/21/05