[TenTec] SWR : Speed Weight Ratio

Tue, 12 Jan 1999 10:54:04 -0800

I'll do this again ... A clock runs, goes tick tick tick at uniformly
spaced moments in time ... (called the clock rate .. ticks/unit of time)
The "space" (amount of time) between ticks is called a space. WOW! A
much
better term would be "timeslot", a period of time between uniformly
spaced
ticks.  Ticks are special .. they are in yer mind as infinitely thin
timeslots, or markers, they have no "space" (Something for your muse!)

You can now fill a timeslot with a MARK (which represents a "signal"
such
as pressing down on your key) and how much of the timeslot you fill is
called WEIGHT.  If you fill the timeslot such that 50% of the time the
mark is there, the weighting is 50%.  A mark that takes of the whole
space between ticks constitutes 100% weighting and this is the ONLY
CORRECT
WEIGHT for CW and anything else is not pure CW! It's the LAW!  (Yes, I
know
CW is a mode and not a code .. don't rag me on it!)  A timeslot that is
100% filled with a mark is called a DOT (anything less or more than 100%
is
NOT A DOT!)  So, we have have two things that make up the code: A SPACE
or a timeslot and a DOT.  Next someone invented three consecutive dots,
that is three timeslots in succession each filled 100%.  They called
this
the DASH.  A dash is 3 dots in sequence without any space!  RATIO is
the measure of the length of the DASH to the length of the DOT, which
for Morse Code is defined and FIXED to be 3.  Or in simpler form:
RATIO = length(DASH)/length(DOT) = 3/1, taking the space or timeslot
to be 1 unit of time ... If you play with ratio the code goes into
pure mush very very quickly ... few ever play with ratio and most
even have the wrong ratio in mind!  Read on ...

Now if you only sent DOTs and DASHes you would have a very dull time,
the
signal would sound like one giant long KEY DOWN ... there is something
missing!  Morse Code is NOT made up of DOTs and DASHes!  There are 3 
elements: The DOT, DASH and SPACE (timeslot).  If you now send a string
of alternating DOTs and SPACEes the "DOT" all of a sudden appears in
yer ear!  The clock runs on it's own set rate (we are not playing with
speed in this discussion) so you have no control over that (in this 
discussion) so you can't change the length of a space or a timeslot.
Hence there appears a "secondary" element of the code, a DOT followed
by a SPACE which we shall call a DIT.  Same thing goes for three dots
in a row followed by a space, i.e., a DASH followed by a space. And we
call this thing a DAH.

We now have the following RULES!!!  (if you violate the rules, you send
MUSH!)

              length(SPACE)=1 by definition.  length(DOT)=1

              length(DASH)=3  length(DIT)=2  length(DAH)=4.    

Now (watch this closely!) .....  RATIO (DASH/DOT) = 3

           but what we really use in our EARS is RATIO (DAH/DIT)=2

Folks "tune up" with the letter V because it is the "3 to 1 letter"
you know, three dots equal one dash ... WRONGGGGG ... take a look:
length(3 DITS) = 6   length(1 DAH)=4  so this "ratio" is 6/4 = 1.5
If you are going to "tune up" and get the timing by sending a letter
that
has an "equal length of dots and dashes" the letter to use is ... QUIZ
TIME!
Figger it out ! (You want the "ratio" be 1).  Folks who design keyers
usually
set DASH/DOT = 3 and there's no changing it ... it's part of the
"hardware"
.... but this is assumes of course that they understand how the code is
put
together in the first place ...

That's the way CW is put together, the only thing now you have to add is
some rules about spacing letters and spacing words ... there are a
defined
number of timeslots between sending letter/numbers/punct things and
betwen
things called words ... and although most people get the interletter
spacing
pretty good, most fail MISERABLY in word spacing.  There is an old
saying,
"Give me good spacing and I can copy anything!"  If you want folks to
oogle
over your fist ... space properly and proper spacing is A LOT LONGER
between
words than you imagine .. look it up ... I'm not telling you what it's
supposed
to be ... go find out and then DO IT!  On the otherhand I have run
across an
occasional op who has not only no word space but NO LETTER spacing as
well,
it's like trying to decode a digial signal having to guess where the
framing
pulse is ... one fella down SA was so good at it it took me twenty
minutes to
finally figger out just his call!  AMAZING "talent"!

SOAPBOX TIME:  Rules that should never be broken and the like ... flame
away
with tonza opinion, but don't sendum to me!  My mind is already made up
...

Every key, keyer in the entire world and the whole UNIVERSE should
be given 100% weighting and LOCKED THERE absolutely no way should it
ever be messed with ... BUG OPS don't have that luxury and so you get
all their "beautiful music" ... (to use a phrase)! This varying of 
weighting usually hugely heavy or longer than 100% to "get the signal
thru noise" is for the most part balony ... a speed change will affect
better thruput anytime than playing with weighting.  A fellow who goes 
to LONGGGG DASHES and LONG DOTS is hugely more difficult to pull thru
than one who sends at varying speeds ... beside the changing of WEIGHT
either manually or electronically causes an even greater problem with
the folk at the other end: you change their "expectation filter"!! , you
are sending something they are already having difficulty in copying and
you add a new twist to the game, having them figger out what new gimmick
you are doing PLUS trying to copy the message ... set WEIGHT at 100% 
and LEAVE IT THERE! Then CUT THE WEIGHT KNOB OFF YOUR KEYER!!!! (There
is
only one exception that I am aware of ... the human ear has better
response
to high speed CW ... like above 45..50wpm ... when the weighting is
DECREASED! very slightly to like 99 or 98 percent.)  If you want to
improve
thruput, change your speed, it's far less of a shock to the other
operator
and you will have far greater success of getting thru ... and it is
usually
FASTER not slower CW that gets thru ... QRP ops should have learned this
long ago ...

          CW is MUSIC, learn to tap your foot and carry a melody ...

....... so sez "W"  (Dave NC7W ... xW0MHS)

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