## A primer on Morse code communication and the requirements to keep it alive
Morse code seems to be rather useless in these times of ubiquitous digital means
of communication, but it is highly appealing if you like to keep communication
independent of electronic go-betweens.
### What is Morse code?
(Note: I won't go into the history of Morse code in this text, and I will only
talk about the so-called "International Code", not the old "American Code"
initially used on telegraph lines. Please consult your favourite Encyclopaedia
for further details!)
Morse code is a representation of the Latin alphabet, numbers (figures) and some
punctuation marks and control signs by long and short signals, intended for
consumption by humans. It is a **ternary** encoding with the following basic
elements:
* short signal followed by a short pause, called "dot",
* long signal followed by a short pause, called "dash",
* character pause,
where the relation of duration is defined as "long" being 3 times "short". The
duration of the character pause is 2 times "short"; as it always follows a
signal with its accompanying "short" pause, the total pause between characters
corresponds to 3 "short" pauses. Words are separated by two additional
character pauses, resulting in 7 "short" pauses in total between the last signal
of the first word and the first signal of the second word.
The ternary nature of Morse code permits characters of varying lengths, and the
encoding was chosen to roughly correspond to the letter frequency of Western
languages; for example, `E` is encoded as "dot", `T` as "dash", `I` as "dot
dot", `Q` as "dash dash dot dash".
### Current Use of Morse Code
While Morse code transmissions were initially the only means to transmit
information by radio waves (before the availability of continuous wave
oscillators), they are now only used by armed forces, radio amateurs, and some
beacon and navigational systems. This is due to the fact that whilst Morse code
allows for communication on very noisy channels, it still requires human
operators, and there exist modern digital transmission systems which can
reliably work under similar noise conditions. Human radio operators are very
expensive, and therefore only armed forces and radio amateurs can afford their
use and at the same time profit from the low technical requirements and high
reliability Morse code offers.
It has the following advantages over other transmission types:
* It requires only a channel capable of carrying binary signals (the ternary
element is defined by timing), permitting use of very simple and consequently
reliable/rugged equipment;
* the channel can be very noisy (the limits depending on the experience and
collaboration of the operators), allowing Morse code to remain usable even under
very bad conditions;
* the bandwidth of the channel can be very low (depending on the desired
transmission speed: for experienced operators and comfortable communication in
the range of 20 to 50 Hz), resulting in very good use of the available spectrum
and permitting "piggybacking" on other signals.
Although best results can be achieved by auditory reception (sound or signals
converted to sound), also visual or even mechanical reception (by feeling
vibration or pressure) is possible. Note that Morse code can even be used to
circumvent sensoric and motoric inabilities due to illness or accidents!
In my opinion, it is therefore very useful and highly recommendable to learn
Morse code, but it should be done with the focus on auditory training, as any
visualization of the signals will prevent the brain from making use of the
musical/rhythmical nature of Morse code.
### Promote Morse Code
Unfortunately, the current volume of clear text Morse code transmissions on the
entire radio spectrum is very low (except for amateur radio), and therefore
there is very little material on air to listen for. This makes it difficult to
get people interested in learning Morse code, as "it is useless", and only radio
amateurs have a chance of using it "for real".
However, it is straightforward to automatically generate Morse code
transmissions with cheap modern electronics, and the almost infinite source of
texts available on the internet can be used for cleartext generation. As it is
much easier (and cheaper) than generating spoken word broadcasts in an appealing
way, it may also be interesting from the viewpoint of distribution of
information independent of big media.
The main problem preventing transmissions are legal restrictions, especially on
frequency bands allowing for long distance communications. But laws in this
respect vary considerably between various jurisdictions, which should be
exploited as much as possible. As an intermediate step, promoting internet
multicasting of cleartext transmissions might be useful, though.
If we want *to keep Morse code alive and promote learning* and use, we should
therefore:
* explore the various national legal possibilities of (radio) broadcasting Morse
code to a larger audience,
* build systems (hard- and software) facilitating automatic generation of
cleartext Morse code transmissions,
* organize people interested in Morse code also outside of amateur radio, with
the focus on keeping communication independent of opaque digital systems.
