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RTTY uses the Murray code and the baud rate is
normally 45, 50 or 75 and transmitted in FSK mode. For those operators that can
read the code it can be read directly on a waterfall display. IE for RY normal
test sequence the elements are R = 2 and 4, and Y= 1 3 5. It can be
read in a similar way to visual morse. This would possibly be a good system to
use if slowed down similar to QRS morse, with all the benefits.
You do not need a teleprinter or any sort of print
display, just read it directly off the waterfall display, 1 ele start, 5
elements info, and 1 and 1/2 elements stop. (total 7-1/2 elements per character)
easy to ID and read.
73 mal/g3kev
----- Original Message -----
Sent: Thursday, January 01, 2009 7:14
PM
Subject: Re: LF: NON MORSE
mal hamilton wrote:
I have been looking around the various HF bands
for NON MORSE acty and find that the old RTTY is the most
prolific mode in use, it looks like the use of other data modes are rare,
perhaps more suited to V/UHF EME work etc.
g3kev
Hello Mal., LF group
i do not agree
with you. I guess if you had taken more time for your
watch of HF bands your conclusions would be different.
it is
sometimes useful to extend time basis for making more reliable
"averages " , hi. in my opinion it is PSK31 as
#1 these days.
Of course from historical reasons rtty dominated
in ether for many years but the last decade has changed
it when DSP
techniques came into play along with PC's in
almost every house etc... . btw, rtty as you know is based on a Baudot
code known before
radio waves were 'discovered' and used to
carry information . the popularity of rtty is based on the
selfsynchronizing properties of the
7bit Baudod code ( 1 start bit
one stop bit + 5 bits for letters/nonletters dot, hyphen....) it is not
arq mode so you can listen to it anytime etc..
like CW which is
also itself selfsynchronizing i.e you know very well when it is started
stopped etc... PSK works the same way - from all
so called
'digital' modes it is like a live qso with its speed similar to
CW and so one and the selfsynchronizing properties due to the varicode of
G3PLX
are great ! that is why , in my opinion psk31 wins these
days. my first psk qso was almost 10 years ago and i work mainly psk on
HF bands tiill now.
I do think it is the most popular
digi mode at present.
Dear Mal, here is one issue more ...
i do
observe the ongoing discussion between you and others concerning the CW vs
other modes. in a moment i will add my comment to this
but in
the form of example of one of my psk qso which i will remember forever.
it was in the early 2000's when the prop was not that
bad
and i had regular(everyday basis) qso with US
stations at the evenings on 14 Mhz . it was an american callsign - i do
not remember it ( but can look into my logbook if you want) but
what i do remember he was 86 years old , all time ( both his work and
his hobby) a CW operator but by that time he was deaf, completely
deaf and he told me" Peter, i can not use my EARS i am a deaf
person i can not use CW anymore but i can use my EYES and due to psk i still
can enjoy my radiohobby" - please, excuse my english but the sense
of the words of this old man is obvious.
so at least two
points are emerging...
1. we have ears we have eyes =
both human senses can be used to 'read' the information
which modulates the radiowave
2. the dsp techniiques are more
superior to CW these days as far as S/N is
concerned
again, HNY 2009 , yours, peter, sq7mpj
qth: lodz, poland
/jo91rs/
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