Epson manual MFJ-1278B MULTI-MODE Basic Operation Amtor Operation, Mode a ARQ, Mode AM Enter

MFJ-1278B MULTI-MODE BASIC OPERATION

AMTOR OPERATION

AMTOR, AMateur Teletype supported by the MFJ-1278B. and mode B.

Over Radio), an error correcting protocol suite, is fully Two modes are available with AMTOR. These are mode A

From command mode, AMTOR modeB is entered by typing:

MODE AM <ENTER>

Note that the MFJ-1278B displays an "a_cmd:" once the AMTOR mode has been entered. This "a_cmd:" command prompt lets you know that you are in AMTOR mode and only AMTOR commands are recognized by the MFJ-1278B. To issue other non AMTOR commands you will have to return to the normal command mode ("cmd:" command prompt) by typing "CTRL-C".

Operation of the Tuning Indicator in the AMTOR mode is the same as all other modes. Simply tune the signal so that the center LED segment of the Tuning Indicator is lit with each burst of AMTOR signal received.

Mode A "ARQ"

Automatic request for re-transmission mode, known as "Mode A", is similar to packet radio in a number of ways.

The calling station must know the ID of the station being called, in order for communications to occur.

The "ARQ"command initiates a link attempt with the station being called. A link attempt in AMTOR, is similar to a CONNECT attempt in Packet.

Mode A is a one-on-one protocol, meaning that it is used for QSOs, and not for calling CQ or broadcasting. (see FEC and SELCALL for more on broadcasting.)

ARQ Mode A introduces a few new terms, "Information Sending Station," (ISS) and "Information Receiving Station," (IRS). In ARQ, a station must be either the ISS or the IRS, and the station that is transmitting data is called the ISS.

One becomes an ISS either by issuing a successful AMTOR call, with the ARQ command, or when the ISS relinquishes control of the link through the changeover, +?. Finally, if an IRS link CHANGE is requested.

Setting up for Mode A Operations

First you should decide upon a selective call identifier and enter it as your MYSELCAL. A