APRS Digipeaters

This page last updated 01/19/2010



Here are some files to help you with setting up your TNC and radio to work as an APRS digipeater.  If you have any questions on the set up your TNC, please contact Mark N9MEA at n9mea[at]wisconsinaprs[dot]net.

You can also check out Bob Bruninga WB4APR's APRS webpage for more information.


TNC Information

Note from Mark N9MEA: I don't agree with backing down the TX delay (TXD in some TNCs) below 300mSec.  I've seen problems with some radios cutting off the beginning of the APRS packets causing the packet to become unusable.  My suggestion is to stick with the 300mSec delay and if you are using older radios that may have antenna relays you may want to consider turning up the delay to 400mSec.

Kantronics KPC3+ version 8.3 and 9.1 - text file
Kantronics KPC3 version 8.2 - text file
Here is the
pin out of the radio connection to the KPC3 and KPC3+
Kantronics KAM, KPC1, KPC2, KPC4, KPC2400
Commands Manual for version 3 firmware
Kantronics KAM, KPC1, KPC2, KPC4, KPC2400
Install Manual  
Kantronics KPC3, KPC3+ firmware version
8.2 manual addendum

I find that it is easier to use Pacterm when programming the Kantronics because it has a separate command line to enter in the commands and functions.

Pac-Comm Tiny2 - text file

MFJ/Vectronics - Requires burning a new firmware chip using UIDigi
1270 series/ 1274/ some 1278 -
Fill-In Digipeater - text file
1270 series/ 1274/ some 1278 -
W2 max Digipeater - text file
1270 series/ 1274/ some 1278 -
W3 max Digipeater - text file

If this TNC is to be used as a stand along digipeater, it will only work as a WIDE1-1 fill-in digi.  If it is to be used as a regular full feature APRS digi, it must be controlled by a computer running the correct software such as UI-View.

UI-View Digipeater Settings
Setup instructions for both a full digipeater and a WIDE1-1 fill-in digi -
pdf file - link

Just a couple of notes about using this set up.  First, increase the DUPE_SUPPRESS_SECONDS to 35 from 30.  UIFLOOD for Wisconsin should be WI, so it should read UIFLOOD=WI.  When entering in the alias information (or sub alias), your call needs to include any SSID that you may be using.

In the Station setup-Beacon comment, use PHG if you want, it isn't necessary.  Also, for Wisconsin, the rest should read Wn, WIn and then the city or town.  The big thing in the Station set up is to enter the correct station icon and overlay.  Use the "S" for a full digipeater and a "1" for a Wide1-1 fill-in digi.  Before you can edit the text file for the full digipeater, you must enable digi  and UI Only in the Digipeater setup.

Open Tracker 2 - This TNC uses the pin out on the radio connector as the Kantronics KPC3 series.  We have the pin out listed below.  Here is a
sample file of a working digi (N9MEA-6 in Adams/Friendship).  Do a right click on the link to the file and do a save as and then save it where ever you save your OT2 files.  If you are using this file, be sure to have the OT2 software and be sure to change the call and position test for your site.
Argent and GE/Ericsson MDX radio - We have this TNC on the GE MDX radio at many sites.  There is a small modification that we do to the TNC because the radio need more transmit audio and that is to remove R3 (30K resistor) and then install the "HI" jumper.  If you remove the jumper, you can hook the TNC to a standard ham radio and not have too much audio driving the mic circuit.

Tiny Trak 4 - Coming soon

Settings for a WIDE1-1 fill in digipeater
Many different TNCs can be used as fill in digis.  These include the PK232, any MFJ, any TAPR-2 clones, any KPC3 or 3+, KPC9612 and many others.  Check out these
settings (text file).

Overlay Characters for Digipeaters
Here is a
list of characters to overlay in the stars that show the digipeaters on the map and what functions they can handle.



Radio / TNC Connections

GE Delta SX or S Connections
Here is a
wiring diagram to go from the Delta to a 5 pin DIN plug for the MFJ TNCs.

GE/Ericsson MDX Connections
Pin Out of the 16 pin option connector

GE Phoenix Connections
Here is information on
wiring a Phoenix to a TNC

Motorola Maxtrac series - Radius M100 series Connections
Here is a
link to the Batlabs Maxtrac/Radius webpage.
Here is
wiring diagram of the Maxtrac/Radius mic jack.
Here is the
pin out of the 16 pin Maxtrac/Radius jack on the rear of the radio.

Motorola Syntor X Connections
Here is a
link to Mike Blenderman's website for making a Syntor X into a packet radio.
Here is a
link to Mike Blenderman's main Syntor X webpage.
Here is a
link to the Batlabs Syntor and Syntor X webpage.  You can get a freeware copy of the SPROG eprom programming software here.

Kantronics KPC3 / KPC3+ Connections
Here is the
pin out of the radio connection to the KPC3 and KPC3+

Anderson Power Pole Power Connections
Here is the
pin out of the standard Anderson Power Pole used by ARES/RACES.


If you have any other information that should be included on this page, please send it to Mark N9MEA at n9mea[at]wisconsinaprs[dot]net.