Specifications

CHAPTER 6
BAUDOT AND ASCII RTTY OPERATION
6.1 Overview
Baudot (pronounced Baw-dough) has been in use for many years. The
five bit Baudot/Murray code was the basis of the Western Union Telex
service and Baudot RTTY (Radio TeleTYpe) is still widely used on the
HF amateur bands. The Baudot character set contains the upper-case
letters, the numbers 0-9 and some common punctuation characters.
Because Baudot has only five bits, it is less prone to errors than
seven bit ASCII. Your PK-900 provides Baudot RTTY at all standard
speeds in use today, including commercial speeds up to 300 bauds.
ASCII (pronounced Ask-kee), the American Standard Code for Information
Interchange has been in use for nearly 30 years. ASCII is a 7-bit
code and was designed to overcome the limitations of the Baudot
character set by including both upper and lower case letters, numbers,
all punctuation as well as many computer control codes. ASCII is not
as popular on the amateur bands, but its operation is almost identical
to Baudot RTTY so we will describe them both in this chapter.
Baudot and ASCII may be operated on Radio Port 1 on the PK-900.
Packet may be used on Radio Port 2 at the same time, so you won't miss
any connects while operating Baudot or ASCII on HF.
6.2 Where to Operate Baudot and ASCII RTTY
Before you can operate Baudot or ASCII RTTY, you must first know where
the activity is. Most RTTY operation occurs on the 20-meter amateur
between 14.08 and 14.10 MHz. RTTY activity can be found on the other
HF amateur bands as well and is most often located between 80 and 100
kHz up from the bottom of the band as it is on 20 meters.
6.2.1 PK-900 Baudot RTTY Parameter Settings
First you must enter the Baudot mode of the PK-900.
If you are using an AEA PAKRATT program, follow the instructions in
the program manual to enter the Baudot mode.
If you are using a terminal, simply type "BAUDOT" or "BA" from the
Command Mode followed by the <Enter> key to enter the Baudot mode.
The PK-900 responds by displaying the previous mode:
Opmode was PAcket
Opmode now BAudot
Your PK-900's front panel LCD display will show the Baudot
operating mode on Radio Port 1 and the SYSTEM COMMAND LCD will also
be on.
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