Epson MFJ-1278B Initial Parameter Settings Summary, What to Expect, Frack, ACKTime, RESPtime

MFJ-1278B MULTI-MODE ADVANCED OPERATION

Initial Parameter Settings Summary

The settings for use at 1200 baud on a VHF FM channel are:

ACKprior ON

SLots3

DEAdtime 33

ACKTime 13

RESPtime 0

If you require a nonzero value for this parameter in order to prevent ACKing individual packets in a MAXframe greater than 1 blast, your DCD circuit is not working. Please get it fixed.

DWait0

DWait should be set to 0 even if there are digipeaters on the channel. The new system will not degrade the performance of digipeaters on the channel because the ACKWAIT can be used by the DIGI.)

MAXframe	1 - 7 depending on channel quality
FRACK	3

The settings to use for 300 baud work on a linear mode HF channel are:

ACKprior	ON
SLots	3
DEAdtime	12
ACKTime	52
DWait	0
RESPtime	0
MAXframe	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.