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.

You are now ready to start APRS and give it some data. Before you do, there are a few things you should know.

Running the program

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.

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