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Hi guys,

I'm doing some repair work on an MFJ-1270C TNC for a local school for the
MIR test this month.  The TNC radio data rate cannot be changed by the dip
switches on the rear.  I am trying to get it setup for 1200 bps.  It
receives 1200 ok, but tries to transmit 9600. JMP 27 is set correctly for
this by the way.  

When I called MFJ they said the 9600 modem was in need of repair and to
send it in for them to work on.  I understand there is one chip on the 9600
modem that controls the switching between the 9600 modem and the regular
1200 modem on the TNC board.  I suspect that it is U20, the 74FC157 chip
but since I don't have a schematic for the modem I am not sure of this. 
The modem is the MFJ 9600 Rev 1.4.  I don't want to send the thing back
just to have them charge labor and parts to change one chip.

If anyone can shed light on this for me please answer direct.  Thanks in

I am still off the satellites waiting for an Azimuth position indicating
pot for my Emoto rotor.  The US distributor didn't have one and ordered it
from Japan.....By ship!!!!

I have faxed the Japanese company and asked if they could send another. By
air direct.  No reply yet.

73, Roy

Internet: w0sl@amsat.org
Home Page: http://home.swbell.net/rdwelch