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OLMEC (OrthogonaL MorsE Code) - circa May, 2002

A Fun Experimental Mode

General Philosophy of OLMEC: - The idea for OLMEC came while reading about old South American civilisations. The Olmecs, Mayas, etc had sophisticated writing and numbering systems. In particular they had a dot and bar system for numbering. I was struck by the similarity between the the dot and bar numbering system and morse code.

Having a quick look at morse code revealed that five (5) tones could be used to encode all the letters and numbers. To show the general idea here is a heavily compressed GIF example (part of the background picture from my OLMEC generating software).

The text OLMEC is shown with its encoding underneath. To represent numbers requires five (5) tones. The OLMEC software (in testing at the moment) generates the tones with a spacing of 1Hz and the basic timing is 10 second/dot. These parameters are suitable for propagation paths with several hops on HF. The duration of a bar is 3 dots (30 seconds). The time between characters is one dot time (10 seconds) and the time between words is 4 dots (40 seconds).

DISCLAIMER: I make no claims about the relative efficiency of this mode compared to other modes and point out that it is a linear mode like PSK31 and requires the same interface. However, I make a few interesting observations after looking at OLMEC signals in poor S/N situations.

Observations of OLMEC: - The length of each character is identical making it easier to locate the extent of an individual character (normal morse is variable length, which is obviously more efficient, but sometimes confusing visually in noise). Because the dot time always occurs in the middle of a bar (when there is one) it is easier to sort out a dot from noise.

Basically, the regular structure of the code gives some temporal clues for the decoding of the eye-brain.

Summary:- A new mode which can be decoded by eye and which uses the familiar (to hams) morse code is presented. The receiving party only needs a copy of Argo or equivalent waterfall spectral display program to be able to decode it (and a morse code decoding sheet if necessary). It is a fun code to play with and no claims are made for efficiency or suitability of the new mode (except for having a bit of fun).