[aprssig] MFJ-1278T TNC2 modification posted

Tim Cunningham tim_cunningham at mindspring.com
Sat Oct 15 11:48:45 CDT 2005


I just uploaded the details for my MFJ-1278 modification. Several people
have been asking for it over the years and I simply had no bandwidth to
document it due to my workload. Hopefully, I covered all the changes in the
document so you can utilize the MFJ-1278 unit as a TNC2 compatible to work
with the UIDIGI firmware.

We have been using the MFJ-1278 for many years with Net-Rom and UIDIGI here
in North Alabama very successfully. The MFJ-1278 is based on the original
TNC2 design but it added extra features that no longer made it an exact TNC2
compatible because the serial port settings, modem port settings, and radio
port settings were controlled in firmware opposed to hard set dip switches.
These are just an example of the electrical changes that deviated the unit
away from the original TAPR TNC2 design.

The modification is posted on the UIDIGI group site in the files area and
the Database area.

If you drop me a message asking questions, please do not expect an immediate
response because my job comes first as it pays the bills. When I have time
to respond I will get back with you, but please read the documentation first
and read it again if you have trouble.There may be some minor differences
between some of the MFJ-1278 revisions that may require some different
changes to make them work. I attempted to cover the major changes required
for the units that I have physically seen. It works very well with UIDIGI.

73's and Good Luck!

Tim - N8DEU
Huntsville, Alabama


This email message is a notification to let you know that a file has been
uploaded to the Files area of the uidigi group.

  File        : /1278_UIDIGI.doc
  Uploaded by : n8deu - Tim Cunningham
  Description : MFJ-1278 TNC2 modification for UIDIGI

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