Discussion:
‘more 3D morse’ (sic) by Brian Howie, UKRAM
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Spike
2017-08-11 22:27:59 UTC
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Over in our 'young sister' group, Brian Howie has posted a link to a
very interesting Masters thesis concerning Morse Code, under the Subject
line ‘more 3D morse’ (sic)

<***@b-howie.demon.co.uk>

The was not much real follow up to this, and even less comments on some
of the issues mentioned that bear directly on Amateur Radio, so here are
a few of Spike’s Picks:



[1] =====

2.2 Morse Code

When copied by a human, Morse code is still considered the most reliable
form of communications. Morse code requires the least amount of power
and the simplest of transceivers.

A human can copy a weak Morse code signal buried in noise, interference,
or jamming. The signal to noise ratio (SNR) required for Morse
communications is minimal compared to the SNR required for voice, or
digital communications. Humans are successful in copying Morse code
because of the brain's audio pattern recognition capabilities. The
brain's pattern recognition capabilities dwarf those of the best pattern
recognition system. Experiments have shown that man requires
significantly less SNR compared to electronic Morse decoders [11].

[11] Montnemery, Peter, et al. "Performance of Electronic Morse Decoders
in Decoding Telegraphy Masked by Noise," Scandinavian Audiology,
24(1):57-62 (1995).

=====

No doubt this paragraph alone explains why Morse, after well over a
century, is still the predominant mode for Amateur contacts. Just look
at the points raised: “most reliable form of communications”; “SNR
required …is minimal”; “man requires significantly less SNR (than)
decoders”. These are very significant advantages.



[2]====

2.2.2

Mental Process of Copying Morse Code.

In order to improve the Morse audio presentation it is helpful to
understand the mental process of copying telegraphy….Further it has been
suggested that those who are musically talented excel at copying Morse
code. The suggestion that those who are musically talented are also
talented Morse operators may show that Morse processing is similar to
musical information processing.

=====

The link between Morse and music is interesting, not least because it
has also been suggested elsewhere that music and Maths are linked.
Interestingly there appears to be no extant evidence linking an ability
in Maths to a similar ability in Morse.



[3]=====

2.3 Optimal Frequency and Listening Level

Source frequency and listening level adjustments must be made to
increase copy accuracy. Recognition is highest when a source is
presented at 500 Hz, level) of 70 dB [10]. For SNR above -7 dB, the
frequency of the Morse source does not effect recognition. Figure 2
shows recognition rates for code presented at 16 wpm as a function of
frequency. Figure 3 shows the median recognition values for 11 subjects
as a function of spl.

[10] Montnemery, Peter, et al. "Recognition of Telegraphy Signs at
Different Listening Levels and Frequencies," Scandinavian Audiology,
21:255-260 (1992).

=====

Personally, this is a fascinating piece of evidence. I have always read
Morse with the audio set fairly low and with a pitch between 500 and 600
Hz. Occasionally, other HF CW-skilled Amateurs have commented on this,
preferring higher sound levels and higher tone pitch, the effectiveness
of which isn’t really borne out in this study.


[4]=====

[4] Figure 2

Digital processing? Look at this and weep. !00% copy at -7dB SNR!
Combine this with the poor performance of digitally-processed Morse, and
demonstrates the considerable advantage that HF CW operators have,
especially when combined with the hugely less complex technology of CW
transmitters and receivers.

=====

With these massive advantages, one wonders why the CW test was
discarded. This is even more significant when it is considered that
there have only been two recorded cases of Morse aphasia [2, 25]
suggesting that the vast majority of the Amateur population are indeed
able but apparently unwilling to learn the straightforward skills
necessary to be competent at Morse. The entire paper makes interesting
reading for all but the Morse-shy.

[2] Ardial, A. "Aphasia for Morse Code: a comment on Wyler and Ray(1
986)," Brain Lang,
30:363-366 (1987).

[25] Wyley, A. and M. Ray. "Aphasia for Morse Code," Brain Lang,
27:195-198 (1986).

An excellent exam paper could be set using this thesis alone as a base.
When combined with the associated projects of building a CW transmitter
and receiver, a 12 wpm Morse test and concomitant training, the
resulting rigour would turn out successful candidates with very greatly
enhanced performance and abilities over and above those of the current
system - which seems to have been designed for the Morseless by the
Morseless.
--
Spike
Bernie
2017-08-11 23:00:56 UTC
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On Fri, 11 Aug 2017 23:27:59 +0100
Post by Spike
With these massive advantages, one wonders why the CW test was
discarded.
There has never Bean a CW test, L'il Burty.
Chris
2017-08-11 23:35:06 UTC
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Post by Spike
An excellent exam paper could be set using this thesis alone as a base.
When combined with the associated projects of building a CW transmitter
and receiver, a 12 wpm Morse test and concomitant training, the
resulting rigour would turn out successful candidates with very greatly
enhanced performance and abilities over and above those of the current
system - which seems to have been designed for the Morseless by the
Morseless.
Both music and morse recognition are fundamentally about rhythm and
having an awareness of it. The rest is memory...

Chris
Brian Reay
2017-08-12 05:50:44 UTC
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Post by Chris
Post by Spike
An excellent exam paper could be set using this thesis alone as a base.
When combined with the associated projects of building a CW transmitter
and receiver, a 12 wpm Morse test and concomitant training, the
resulting rigour would turn out successful candidates with very greatly
enhanced performance and abilities over and above those of the current
system - which seems to have been designed for the Morseless by the
Morseless.
Both music and morse recognition are fundamentally about rhythm and
having an awareness of it. The rest is memory...
Chris
The paper Spike refers to is from 1995, things have moved on, although
even by then the military had largely pushed Morse aside. Rather odd
Spike didn't know that, given his claimed career history.

In fact, there were already moves at WARC around then to remove the
Morse requirement precisely because it had already been recognised that
the excuse amateurs may need to be 'asked to move' by other users was
redundant. Given the lag in such things, Morse was long gone as a
serious mode in either military or commercial use, no matter what Spike
wants to believe.

As for an exam question.

This is old technology. He clearly wants to churn out little clones of
himself who relive the days of 19 sets and BC221s. Odd for a G7.
--
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Spike
2017-08-12 10:27:07 UTC
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Post by Chris
Post by Spike
An excellent exam paper could be set using this thesis alone as a base.
When combined with the associated projects of building a CW transmitter
and receiver, a 12 wpm Morse test and concomitant training, the
resulting rigour would turn out successful candidates with very greatly
enhanced performance and abilities over and above those of the current
system - which seems to have been designed for the Morseless by the
Morseless.
Both music and morse recognition are fundamentally about rhythm and
having an awareness of it. The rest is memory...
In a musically-talented family, I'm the black sheep. Tone deaf, can't
read music, little sense of rhythm, can't dance, cant play an instrument
even by ear. I hated 'music' as a subject at school, from infants to the
start of the GCE courses. On family music nights, I was relegated to
page-turning, being clued in by a nod from one of the performers. Now,
CW is another matter entirely..... In my early teens I acted as the
logger for a well-known G5+2 operating the local club's HF Field Day
station for the first 4-hour shift, which was the really busy one. He'd
work a station and call out the callsign and signal reports. After a bit
he realised I'd already filled in the log as we were going along.
Pausing only to borrow my headphones (re-cabled WS19 ones) because they
were more comfortable than his, we settled down to the rest of the
shift...We beat our other local club, which had more members, enabling
an overnight shift that our small club couldn't manage. ISTR Club Nights
had only a dozen or so members.
--
Spike
Roger Hayter
2017-08-12 00:17:12 UTC
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Post by Spike
Over in our 'young sister' group, Brian Howie has posted a link to a
very interesting Masters thesis concerning Morse Code, under the Subject
line 'more 3D morse' (sic)
snip details
Post by Spike
An excellent exam paper could be set using this thesis alone as a base.
When combined with the associated projects of building a CW transmitter
and receiver, a 12 wpm Morse test and concomitant training, the
resulting rigour would turn out successful candidates with very greatly
enhanced performance and abilities over and above those of the current
system - which seems to have been designed for the Morseless by the
Morseless.
A lot of what you say is true, especially for amateur use. But the
author ignores computer/DSP based signal recovery from noise which
trades rate of passing information for much decreased minimum SNR
figures, 20-30db better than morse can manage. These techniques, as we
know, are now routine in amateur radio for various purposes.

Again, this paper is more than 20 years old, and doesn't seem to have
influenced military practice. Though we don't know exactly what happens
in intelligence circles, there are probably better clandestine
communication processes than HF morse.

So while it does illustrate the unique value of morse for amateur real
time communication I don't think you have made a very good case for
reversal of recent licence changes. But promotion of morse is well
worthwhile.
--
Roger Hayter
Brian Howie
2017-08-12 08:19:14 UTC
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Post by Roger Hayter
Post by Spike
Over in our 'young sister' group, Brian Howie has posted a link to a
very interesting Masters thesis concerning Morse Code, under the Subject
line 'more 3D morse' (sic)
snip details
Post by Spike
An excellent exam paper could be set using this thesis alone as a base.
When combined with the associated projects of building a CW transmitter
and receiver, a 12 wpm Morse test and concomitant training, the
resulting rigour would turn out successful candidates with very greatly
enhanced performance and abilities over and above those of the current
system - which seems to have been designed for the Morseless by the
Morseless.
A lot of what you say is true, especially for amateur use. But the
author ignores computer/DSP based signal recovery from noise which
trades rate of passing information for much decreased minimum SNR
figures, 20-30db better than morse can manage. These techniques, as we
know, are now routine in amateur radio for various purposes.
The ear-brain DSP has an effective bandwidth of about 30Hz, so using a
2.4KHz bandwidth , Morse can be decoded to about -19db. WSPR can do
about -27dB , The new FT8 mode is about -20dB. QRSS can have dots
lasting 30 seconds. All this assumes steady signals and white noise,
which is rare,

The snag with signals you can't hear is that contacts have to be
pre-arranged to some extent, otherwise you're into SETI territory.

Brian
--
Brian Howie
Spike
2017-08-15 07:36:01 UTC
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Post by Brian Howie
The ear-brain DSP has an effective bandwidth of about 30Hz, so using a
2.4KHz bandwidth , Morse can be decoded to about -19db. WSPR can do
about -27dB , The new FT8 mode is about -20dB
And that's at only 50% recovery! And, additionally, a far more complex a
system.

CW beats it by a country mile.
--
Spike
Brian Reay
2017-08-15 07:59:38 UTC
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Post by Spike
Post by Brian Howie
The ear-brain DSP has an effective bandwidth of about 30Hz, so using a
2.4KHz bandwidth , Morse can be decoded to about -19db. WSPR can
do about -27dB , The new FT8 mode is about -20dB
And that's at only 50% recovery! And, additionally, a far more complex a
system.
CW beats it by a country mile.
That is a remarkably naive claim.
--
Suspect someone is claiming a benefit under false pretences? Incapacity
Benefit or Personal Independence Payment when they don't need it? They
are depriving those in real need!

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