Glossary

AGWPE: A program that allows the operator to use his sound card as a tnc or connect multiple programs to a single tnc. It can be downloaded from http://www.forthnet.gr/sv2agw/start.htm.

APRSd: An APRS server program that runs on the LINUX operating system. APRSd is a text based only program. It is intended to allow APRS stations to connect to the server and receive or feed data from other APRS programs.

Bell 202 Format:  This is the tone format used over the air to communicate packet burst.  The tones used are 1200 Hz and 2200 Hz. 

Converse Mode:  when you are in this mode any time you send a carriage return the tnc will transmit the data that is entered in.   After you are finished with sending tnc parameters in terminal mode you wind up here.  When the APRS program you are using sends data you basically use the tnc for a A/D converter.  The program handles everything except digipeating and tnc specific items like you mailbox.

Digipeater(digi):  The easiest way to think of a digipeater is as if it is a simplex repeater.  In reality this is exactly what it is and does.   The digi repeats any station that has the digi's call in its unproto path.  A digi may be setup to respond to a variety of calls or tactical calls.

Protopath:  This is a shortcut for unprotopath.  This setting is how you take advantage of digipeaters.  You can use specific call signs or an alias such as WIDE or RELAY.  When you are needing any sort of range beyond your local area the usage of digis via the unproto path can greatly extend your range.

Tactical calls:  The usage of tactical calls can occur when you would rather look for say ROVER 1 instead of trying to remember who's callsign is ROVER 1.  Care must be used when using a tactical call format.  You will still need to use your callsign every 10 minutes.

Terminal Mode:  This mode controls how you interface to the TNC.  Terminal mode is were you send commands to the tnc.  This is important since you change various parameters.  You will end up in converse mode when you are done sending to the tnc.

TNC:  Terminal Node Controller.  A tnc is a rf version of a modem.  It converts the digital signals that your computer uses to audio tones and back.  The format used for these tones at 1200 baud is refered to as Bell 202.

UI Frames:  These are packet frames that do not require acknowledgement.   They are more of a broadcast than anything else.  APRS operates on the usage of UI Frames except for messaging.  Messaging uses conventional error correction.

Unprotopath:  This setting is how you take advantage of digipeaters.   You can use specific call signs or an alias such as WIDE or RELAY.  When you are needing any sort of range beyond your local area the usage of digis via the unproto path can greatly extend your range.

X-APRS: This is a Linux based program for the X window enviroment. It is capable of a graphical view using the maps that you can download from ftp://aprs.rutgers.edu/pub/hamradio/APRS/.

Xastir:   This is another Linux based APRS application.  It uses the maps that are on the ftp://aprs.rutgers.edu/pub/hamradio/APRS/ site and is free to the ham community.  This program is independent of the Sprouls X-APRS program.  It can be downloaded at the TAPR software area.

If you have heard a term used in APRS or Packet operations that you are unfamilar with please email me.  I will give you the definition and place it here on the site so someone else may learn from it.