MFJ-1278B MULTI-MODE

ADVANCED OPERATION

Some HTs and every Azden PCS-2000s that I have ever seen are incapable of operating in a LAN which is using a 300 millisecond setting for this parameter.

Most HF linear mode radios are MUCH faster than VHF FM radio. A reasonable setting for HF work is 120 milliseconds (DEAdtime set to 12). This should work fine with virtually any HF radio stable enough to consider using on HF packet.

ACKTIME 0 - 250 (also 10 millisecond increments)

This represents the time required to send a response frame (with no I field appended) at the baud rate being used on the radio port.

The current 100 millisecond default is close but should be adjusted for 1200 baud work to 130 milliseconds (ACKTime set to 13).

For 300 baud HF work this parameter should be set to 520 milliseconds (ACKTime set to 52).

SLOTS n 0<=n<=127

This parameter determines how many sides are on the slot time dice. SLOTS represents an n+1 sided dice the MFJ-1278B "throws" before transmitting. The SLOTS command allows any number of slots from 1 thru 127 to be defined.

SLOTS (n)

REMARKS

1

Disables Slotting

2

 

4

This should be the default setting

8

Use only if the channel is VERY busy.

16

VERY VERY VERY busy!

32

You get the idea.

64

 

128

Might as well print it out & send it in the mail.

The value used on a particular channel should be agreed on by the channel users. Access to the channel will be equitably distributed among all users if everybody is using the same value for the SLotmask and DEAdtime parameters.

The idea is to pick a value large enough that the probability of two queued up stations picking

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Epson MFJ-1278B manual Slots n, Remarks