MFJ MFJ-1270C, Системное руководство

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MFJ-1270C/1274C MANUAL ADVANCED OPERATION
Page 95
DEA dtime 12
ACKT ime 52
DW ait 0
RESP time 0
MAX frame 1
FRACK 8
What to Expect
This modification to the protocol is compatible with stations using the current
protocol in the following respect. A station using the new protocol will not
degrade the channel for users of the current protocol. So there is nothing wrong
with firing up the new stuff on a channel where the majority of the users aren't
yet using it. You will be able to communicate with users of the other system
without difficulties.
However, if the users of the old channel access procedures have DWait and
RESPtime set to 0, they will tend to hog the channel from users of the newer,
more polite access system.
Therefore, for purposes of testing the effect of the new system on channel
throughput, if there are stations on channel which are NOT using the new
system, they should set their DWait value to one that is compatible with the
new system users. A reasonable DWait setting for 1200 baud use would be 73.
For 300 baud work, it would be 76.
While these settings seem extremely long, they will assure that the stations NOT
using the new protocol always get a shot at slot #1. With these settings, the users
of the NEW protocol will occasionally capture the channel.
Settings of 43 for 1200 baud and 64 for 300 baud could be used to assure that
stations NOT using the new protocol always have a shot at slot #0. This will
result in users of the new protocol almost never being able to capture the channel
unless all traffic from users of the old protocol has been cleared. This should
NOT be done unless ALL stations are using some type of slotted channel access
procedure with compatible numbers of slots and compatible slot times.
Remember that the objective of the new channel access procedures is to increase
aggregate throughput for the CHANNEL, not necessarily for an individual user
(not even you!). It may seem to you at first when you get on a very busy channel