TNC Configuration settings.

    This is the page to look at for TNC settings for APRS.   The majority of my experience is with the KPC3, KPC3+, KAM, PK12 and some on the MFJ1270 and 1278.  The MFJ TNCs are refereed to as TAPR II clones.  When you hear the phrase TAPR II clone it is referring to the second  TNC that TAPR made.   There are two versions of TAPR TNCs.  The TAPR I and the TAPR II.   The TAPR II is probably the most mimicked TNC.   Both AEA and MFJ have produced clones.  If your docs on your TNC say TAPR II clone then the settings are generic.  The settings that work for the TAPR II clone don't always work on clone TNCs.  The KPC3, KPC3+, KPC9612, KAM series and PK12 are not clones.  They have a different set of instructions than the clones.  Depending on your out look one is easier than the other. 

    You need to ask yourself several questions if you decide to buy a TNC. 

        1.) Am I going to be a fixed station?

        2.) Will I be a mobile station?

        3.) Do I buy new or used?

    These may seem like simple questions and fundamentally they are.  The biggest issue from a functional standpoint is stationary verses mobile.  If you run a stationary setup then in reality any TNC will work out.   All the TNC needs to be able to so is support AX.25 version 2.  Unless you have a TAPR TNC I then this is not a problem.  Most people are running AX.25 ver 2 anyway and if not you really should be. 

    If you are intending to run a mobile station then you have many ways to go.  This also prompts more questions you need to consider.

        1.)    Do I run a tracker or use a laptop?

        2.)    If I run a tracker do I want to use a TNC, MIC-E or a PIC-E?

    Let me first address laptops in the car.  Several issues come up when you are running a laptop mobile.  The biggest is power.  As you probably know, cars and trucks don't come with 115 VAC.  For those of you with cigarette lighter adapters for you laptop this is a non-issue.  If you don't have the adapter you can run on the batteries, which may at best get you 2 hours, or purchase an inverter.  An inverter is great for obtaining 115 VAC but can create serious noise on you DC power in the car.  The best thing you can do is make sure you have filtering to kill any noise.  Spacing the inverter as far from the power for the TNC and radio helps also.  The noise an inverter can place on the DC power can be high enough to keep you tones from being decoded.  Trust me on this.  Both myself and N5JZ have been victims of this.  You only other concern is serial ports.  Most laptops come with only one port.  You have 3 ways to get around this.

    A.  Purchase a PCMCIA card that will give you the second, possible 3, serial port(s).

    B.  Run the HSP cable.  Click on the link for more info.

    C.  Purchase either the KPC3+ or the AEA PicoPacket.  I will cover this in detail below.

    Any of the options next to HSP will cost you around $150 dollars.

Trackers

   Trackers are semi simple.  To run a tracker you will need the following equipment:

    1.)  GPS receiver with data output abilities.   Be sure the receiver outputs NMEA 0183.  Currently the Delorme Earthmate is not usable.  It is running a proprietary format.

    2.) TNC, MIC-E, or PIC-E

    3.) Radio, don't forget the radio.

    4.)  Cables.

    I can address many issues on cabling but for now I will leave it simple.  Your cabling needs will vary with the TNC you choose.  For the Kantronics and the AEA PK-12 TNCs you will need to have a DB9 on the end of the cable and a 9 to 25 adapter if you input the data on the db25 connection.  If you have a KPC3+ you can input GPS data at the db25 or the second serial port.  I currently don't ahve information ont he pico-packet.  I intend to add block diagrams soon. 

    For a MIC-E you have two options.  You can run an external GPS or purchase a GPS engine and install it in the MIC-E.   If you run the external GPS you have another 2 options.  You can input it on the db9 on the back or a 1/8" stereo jack.  If you go the db9 route you need to be careful of the cable.  Some of the pins on the MIC-E have voltages present for inputs from other devices and can damage a serial port.  You have to build a progamming cable for the MIC-E but it will be a "null modem" cable so it will not work for GPS input.

   PIC-E has simular considerations but offers more flexable options.  You will need a db9 for GPS input.  There is a programming port on PIC-E but it uses a regular cable with db9s on it.  Refer to TAPRs web site for info on PIC-E.

TNC Parameters

note:  before talking to the tnc, check your baud rate and verify 8,n,1. 

Stationary locations

    Let me backup one step to the stationary setup first.   I will address the trackers next.  Stationary stations dont require fancy setups.  Some of the TNCs do have certain modes you need to be out off to make APRS work right.  Always make sure you are in Termainal Mode.  The reason for terminal mode is simple, tnc configuration.  Before you get on the APRS frequency you need to use the tnc needs to be told various different things.  Your software package should have files for most tncs.  Tell the software what you and it will be handled for you.  You may want to review the file before you start the program and look for anything you wnat to have set differently.  You need to be careful when doing any editing.  Some parameters can't be changed others can.   

Mobile Stations

   I will address MIC-E and PIC-E first.  Most of the information on these items is on the TAPR web site.   MIC-E and PIC-E are transmit only devices.   Software comes with the MIC-E to program it and the software for the  PIC-E is on the TAPR software web site.   If I see enough requests I will put up a MIC-E and PIC-E page.

 

    TNCs are a different manner.  Due to the different tnc setting I will have links to most referance material.  My suggestion is that you creat a text file with the parameters to program a tnc as a tracker.  You can then use a terminal program to send teh congifuration to the tnc.  I have used Comit and Hyperterminal with success.  That way you can change the text file and then send the new config to the tnc without all the typing. 

Kantronics TNC's

    The KPC3 and KAM are offered in 2 different flavors.   The KPC3, KAM,  KPC3+ and the KAM+.  There are big differances between a + version on the older version.  The + versions contain a secondary serial port that can configured to accept Weather input or GPS input.  The older versions require the WX or GPS to be input on the DB25 (terminal) connector.  The older versions work fine as a tracker but have one flaw.  They dont allow you to view the receive side of the APRS network.  The + versions allow you to connect the DB25 (terminal) port to a laptop so you can view and send messages when they are not in GPS mode.

    You want to be running my most current version of firmware you can obtain for you TNC.  The older KPC3 current firmware version is 8.2.   The current KPC3+ version is 8.3.  The version 8.3 is specific to the + version due to the second serial port Starting with 8.2 an important feature was installed, Callsign substitution.  Version 6.0 for the KPC3 is what enabled tracker abilites.  If you have 6.0 or higher you can use you KPC3 for a tracker.

I have linked 2 different configuration files, one for a tracker as a KPC3+ and the other for a digi using a KPC3 and version 8.2.

Tracker

Digipeater