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July 1974 Popular Electronics
 Table of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
from
Popular Electronics,
published October 1954 - April 1985. All copyrights are hereby acknowledged.
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When you think about it,
the speed at which a human being is able to accurately copy Morse code is limited
by the same kinds of processes that limit the speed at which binary data can be
sent between electronic transceivers (modems). Noise introduced into the signal
at both the transmitting and receiving ends or in the transmission path connecting
the two, degrades the ability of the receiver (electronic and human) to discern
between a "1" and a "0." It can take the form of electrical or audio
interference and distortion. Phase noise in the electronic realm is sort of the equivalent of an
irregular sending human hand that cannot maintain equal dwell times for dits and
dahs, thus making the recognition of characters error-prone. The
operational speed of circuitry on an electronic assembly can also limit the
speed at which Morse code can be copied similar to how a particular person's
gray matter can limit his comprehension speed. One Navy lieutenant
in the article stated, "There may be a certain type of individual who can copy fast
code and a certain type who can't." Of course upon reading that line I immediately
thought of the joke declaring, "There are 10 types of people in this world: Those
who understand binary and those who do not." To apply that here, the title could
equivalently be interpreted as, "How to Break the 2-Words-Per-Minute Code Barrier."
How to Break the 10-Words-Per-Minute Code Barrier
 By Richard Humphrey
Lucky is the radio amateur who doesn't "plateau out" somewhere around ten words-per-minute
when he's learning code. There may be a fortunate few who march right up to 20 or
30 wpm without a break, but most of us make it to 10 wpm literally in a matter of
days, then struggle for many months to get up to 15 wpm solid copy so we can be
sure of hacking 13 wpm when we go up for our General. Once definitely past the 10
wpm "hump," progress is seldom a problem.
Hams aren't the only ones bothered by the CW plateau. The Navy, Army, Coast Guard,
and Air Force all have their difficulties in getting their radio-operator trainees
off the 10 wpm dime. When asked if the Army had a problem, Colonel A.J. Sullivan
in Washington said:
"Yes we do. Approximately 60% of trainees reach a hump somewhere between 10 and
13 words-a-minute. Our goal is to raise them to 15," he said, "and often we're able
to get them to go as high as 25 and 30 words-a-minute." Col. Sullivan went on to
explain how the Army did it. "The first way is to have the student and instructor
analyze error patterns and then determine remedial patterns to correct them in the
student.
"The second way," he continued, "is to analyze individual rhythm patterns and
make recommendations to improve these. The third thing is to try and get these students
to copy 'behind' one or two characters so that they might be able to comprehend
a whole word instead of a letter at a time."
A spokesman for the U.S. Navy, Lt. Tim Mennuti, echoed Col. Sullivan. "It takes
three weeks to peak out," he said, "at which point the average person has reached
12 to 14 words-per-minute." Mennuti added, "The problem is that over 14 words-per-minute
there are no breaks between letters." It appears the Navy considers the "hump" serious
since we understand the training program is undergoing considerable revision.
Everyone interviewed agreed on one of two positions: either (a) the plateau was
caused by reaching a speed where you had to stop copying letters and start copying
words or (b) the "letter-to-word" transition was a coincidence and the reason for
the "hump" had to be found elsewhere. The Navy seems to favor the latter view. "Apparently,"
said Mennuti, "there's some psychology connected with this thing that we didn't
have before. What we're finding out," he explained, "is there may be a certain type
of individual who can copy fast code and a certain type who can't."
Strangely, two things which might be expected to have had an effect on an almost
auditory process such as learning CW seem not to have affected it at all: the increasing
use of audio-visual aids in teaching and the tremendous impact of television on
those who have been coming into the military. The generation which has been studying
code for the past several years are, say the experts, "picture" oriented rather
than "word" oriented. One might expect that hams and others cramming code today
would be having more trouble. But Col. Sullivan says the percent of those hitting
the "hump" hasn't changed "in the last 20 years."
Psychologists and authorities in the business of teaching brought up the point
when they were interviewed that getting past the 10 wpm plateau wasn't a "learning"
problem but a "fluency" problem. Obviously, they said, if you can copy and send
ten words-a-minute, you know the code. The point was also made that gaining fluency
in code might be similar to gaining fluency in a foreign language. If you learn
a foreign language by "reading" it - in high school or college, for instance - you
will usually have tremendous difficulty in speaking (or understanding) the language
fluently. You will find that you translate from the foreign tongue into your own
language, absorb the information, form an answer, in your own language, translate
the answer into the foreign language, and then say it. To gain any fluency whatsoever
you must think in the foreign language.
But how do you "think in code?"
Here, the experts and authorities as well as military instructors and radio amateurs
are more-or-less in agreement. Number one on everyone's bugaboo list: don't sit
down and learn the code before you start listening to it! Many hams fall into this
bottomless pit. The CW trainee in the military has usually been sitting there for
three hours with the cans on his head listening to taped copy before someone tells
him what it is he's doing. Even so, six out of ten plateau out somewhere around
10 wpm, according to the Army. The attrition rate among radio amateurs must be tremendous.
One instructor put the problem this way:
"When you find yourself hearing dah-dit-dah-dit and saying 'Aha, that's a C'
and then writing it down, you're in big trouble. It's got to be instantaneous,"
he said. "You hear it, you write it. No translating!"
The way you transcribe CW may also have a direct bearing on the 10 wpm hump.
Without exception, everybody agrees that the best way is to use a typewriter. For
two reasons. First, the mental attitude you have when you learn to touch type is
quite similar to what it should be in learning code. You're not translating. You
learn by rote that the right forefinger goes there and the left forefinger goes
here for this letter or that letter. You're not falling into the bad habit of reading
a letter, looking for it on the keyboard, then hitting it.
Second, copying by hand in capitals will limit your speed to around 15 wpm. Long-hand
script will only take you to 25 wpm or so. The only thing limiting your code speed
when using touch typing is your typing speed. A 40-wpm typing speed in only fair.
A 40-wpm speed in copying code is very good. (It's undoubtedly no coincidence that
of the Air Force's 630 hour CW course, 435 hours are devoted to "touch typing and
transcribing International Morse code with a typewriter.")
The various tapes and records on the market to teach you the code undoubtedly
have some value. The unanimous comment from radio amateurs is that they'll memorize
each tape or record after a few playings and once this has happened the recording
is useless. Tapes work out fine for the military because they can afford thousands-of-hours
of it so there's little chance of copy memorization. Hams usually aren't so affluent.
What to do if you "studied" the code before you began listening to it? You can
try the Army's recommendation of "copying behind" to try to progress from letter
copying to word copying. Or you can try the method used by a former Navy Chief Radio
Electrician.
"My hump was around nine-a-minute," he says. "It made me mad. I just kept at
it. I copied until my eyes fell out. I even copied Russian and Spanish code, though
I didn't understand it. Later, aboard ship, they tested me on taped copy and I made
9 words-a-minute.
To many would-be hams, all this insistence on an "antiquated" form of communications
is ridiculous. With FM, SSB, facsimile, and other things to come in the future,
they may be right. But CW is still the simplest form of long-range communications.
Because when you are using CW, you can cut through QRM with modest power, a minimum
number of components with simple antenna, and troubleshooting and repairs can be
made with almost no training. CW is a unique ease of the Old Gray Mare being just
as good as she "used to be."
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