MFJ-1270C/1274C MANUAL BASIC OPERATION
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cmd: CONNECT N2WX VIA NK6K, KV7D
You specify the digipeaters in the order you would encounter them going from
your station to the station to which you wish to connect.
Your station can also act as a digipeater for other stations. This doesn't require
any special actions on your part -- the MFJ TNC will do everything
automatically. If your station is digipeating, you may occasionally notice your
transmitter keying during lulls in your own conversations.
Unsuccessful Connections
Sometimes you will initiate a connect sequence that can't be completed. The
station may not be on the air, or it may not be within range of your station. You
may have even mis- typed the other call sign. If the MFJ TNC does not get a re-
sponse to its first connect packet, it will try again. You can control the number
of attempts the MFJ TNC will make with the command RETRY. The default
number of retry attempts is 10. If the MFJ TNC doesn't get an answer after this
number of transmissions, it will give up and display the message
*** retry count exceeded
*** DISCONNECTED
The retry count is also used once the QSO has started. Each transmission sent to
the other station is "acknowledged," or ACKed by the other station, and vice
versa. The ACK means that the packet was received and that the CRC checksum
indicated that it was received without errors. This is the means by which packet
radio can ensure error-free communications. Sometimes a packet won't be
received correctly by the other station, either because of accidental interference
from another packet station (a collision), or because of other channel noise. If
the MFJ TNC doesn't get an ACK soon enough, it retransmits the packet and
increments the retry count. If the count set by RETRY is exceeded, the MFJ
TNC will automatically disconnect and display the same message:
*** retry count exceeded
*** DISCONNECTED
The automatic disconnect feature keeps a MFJ TNC from indefinitely
retransmitting a packet and tying up the channel under hopeless conditions. For
example, an intermediate digipeater might have been shut down, or the RF
channel might have deteriorated to the point of being unusable. The other
operator might have even turned off his station without disconnecting. If you
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