Kantronics KAM 98, Руководство пользователя

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Step 10. The “HELLO” packet, including address information
(i.e., to, from, via) and other control information, is now
on the air, where it may be correctly interpreted by all
appropriately configured (i.e., AX.25 packet) stations
that receive the signal.
Step 11. KBØNYK is on the air and is running AX.25 packet, but
it is too far away from WØXI to pick up the signal, so
does not get the message as it is sent from WØXI.
Step 12. As we know from the “connection,” already established,
intermediate station NØGZZ, an AX.25 packet radio sta-
tion, is on the air, and is close enough to receive the ra-
dio burst sent by WØXI. It receives the burst of radio
signals from WØXI and passes the audio signals on to its
TNC for processing. The TNC transforms the signal
from audio to digital, analyzes the series of 1’s and 0’s in
the incoming bit-stream, and identifies the burst as an
AX.25 packet of information containing the message,
“HELLO.”
Also, and most significantly, NØGZZ registers that the
packet designates NØGZZ as the first (and only) inter-
mediate station on a path between a source, WØXI, and
a destination, KBØNYK. As a fully-functioning AX.25
packet station, NØGZZ knows what to do: it sends the
message back out over the air (i.e., digipeats it), where it
may or may not be received by its intended destination,
KBØNYK. Before doing so, it marked its call in the
packet to indicate to others that it had seen the packet
and had sent it on its way.
Note: Since a “connection” has been established, we ex-
pect the message to get through, but each packet is pro-
cessed separately, and each must make it on its own.
Step 13. As we know from the “connection,” already established,
KBØNYK, an AX.25 packet radio station, is on the air,
Packet Communication Introduction
KAM’98 v 8.3 27 User’s Guide