Tag: morse

  • Morse Palindromes, or CQ Christian Bök

    The longest palindrome in Morse code is “intransigence””, and it was on

    First off, here’s the Morse code for the word intransigence:

    ·· –· – ·–· ·– –· ··· ·· ––· · –· –·–· ·
    i  n  t r   a  n  s   i  g   e n  c    e

    If you look at it as a simple stream of dits and dahs, then yes, it’s palindromic. But, like comedy, the secret of Morse (or CW) is timing. It’s important to include the spaces between the keyings, or letters become hard to identify as they run together. For a word to truly sound palindromic, it would need to have the same spacing too, and thus have to start and end on Morse codes that were mirror-images.

    Not only that, but you get codes which when reversed, become another letter. a (·–) becomes n (–·) when reversed. So things are getting more complex, as we’ve now got to think of:

    1. Words which are both palindromes in the English and Morse code;
    2. Words which are palindromes in Morse, but not when written in English.

    With only Convert::Morse and words to guide me, here’s what I found.

    Firstly, here’s a Morse code table for reference:

     ! → –·–·––           3 → ···––          a → ·–          n → –·
     " → ·–··–·           4 → ····–          b → –···        o → –––
     ' → ·––––·           5 → ·····          c → –·–·        p → ·––·
     ( → –·––·            6 → –····          d → –··         q → ––·–
     ) → –·––·–           7 → ––···          e → ·           r → ·–·
     + → ·–·–·            8 → –––··          f → ··–·        s → ···
     , → ––··––           9 → ––––·          g → ––·         t → –
     - → –····–           : → –––···         h → ····        u → ··–
     . → ·–·–·–           ; → –·–·–          i → ··          v → ···–
     / → –··–·            = → –···–          j → ·–––        w → ·––
     0 → –––––            ? → ··––··         k → –·–         x → –··–
     1 → ·––––            @ → ·––·–·         l → ·–··        y → –·––
     2 → ··–––            _ → ··––·–         m → ––          z → ––··

    From that, you can see that the letters which have symmetrical keyings are:

     " ' ) + , - 0 5 ; = ? e h i k m o p r s t x

    So are there palindromic words composed only of the letters E, H, I, K, M, O, P, R, S, T & X? Here are the ones in my words file, longest first:

     sexes rotor toot sees poop peep kook tot
     tit SOS sis pop pip pep oho mom ere eke

    (Somewhere, the ghost of Sigmund Freud is going “Hmm …”)

    When encoded, rotor (·–· ––– – ––– ·–·) has more dahs that sexes (··· · –··– · ···), so takes longer to transmit. So rotor is the longest word that’s palindromic in both English and Morse.

    The characters which have valid Morse codes when reversed are:

     " → "             8 → 2             l → f
     ' → '             9 → 1             m → m
     ) → )             ; → ;             n → a
     + → +             = → =             o → o
     , → ,             ? → ?             p → p
     - → -             a → n             q → y
     0 → 0             b → v             r → r
     1 → 9             d → u             s → s
     2 → 8             e → e             t → t
     3 → 7             f → l             u → d
     4 → 6             g → w             v → b
     5 → 5             h → h             w → g
     6 → 4             i → i             x → x
     7 → 3             k → k             y → q

    Note how 1…9 reverse to 9…1. c, j & z don’t stand for anything backwards.

    So, with only minimal messing about, here are the words that are palindromes in CW:

     ada → nun              ads → sun              ages → sewn
     ago → own              ail → fin              aim → min
     ana → nan              ani → ian              ant → tan
     ants → stan            boa → nov              eel → fee
     ego → owe              eire → erie            eke → eke
     emir → rime            emit → time            ere → ere
     erie → eire            eris → sire            eros → sore
     etna → nate            fee → eel              feel → feel
     fever → rebel          few → gel              fin → ail
     fins → sail            fool → fool            foot → tool
     foots → stool          footstool → footstool  fop → pol
     gel → few              gem → mew              gets → stew
     gnaw → gnaw            goa → now              gob → vow
     gog → wow              got → tow              hoop → pooh
     ian → ani              ids → sui              kans → sank
     kant → tank            keep → peek            kook → kook
     kroger → rework        leer → reef            leif → lief
     lief → leif            loops → spoof          meet → teem
     mew → gem              min → aim              mir → rim
     mit → tim              mom → mom              moor → room
     nan → ana              nate → etna            nerd → urea
     net → tea              nib → via              nit → tia
     nov → boa              now → goa              nun → ada
     oho → oho              otto → otto            outdo → outdo
     owe → ego              own → ago              owns → sago
     peek → keep            peep → peep            pees → seep
     pep → pep              per → rep              pets → step
     pip → pip              pis → sip              pit → tip
     pol → fop              pooh → hoop            poop → poop
     pop → pop              ports → strop          pot → top
     pots → stop            queer → reedy          quit → tidy
     rebel → fever          reedy → queer          reef → leer
     regor → rower          remit → timer          rep → per
     rework → kroger        rim → mir              rime → emir
     robert → trevor        room → moor            rot → tor
     rotor → rotor          rower → regor          runs → sadr
     sadr → runs            sago → owns            sail → fins
     saints → stains        sangs → swans          sank → kans
     sans → sans            seep → pees            sees → sees
     sewn → ages            sexes → sexes          sip → pis
     sire → eris            sis → sis              sling → waifs
     sloops → spoofs        sore → eros            sos → sos
     spit → tips            spoof → loops          spoofs → sloops
     sports → strops        spot → tops            spots → stops
     stains → saints        stan → ants            step → pets
     stew → gets            sting → waits          stool → foots
     stop → pots            stops → spots          strop → ports
     strops → sports        suds → suds            sui → ids
     sun → ads              sung → wads            swans → sangs
     swig → wigs            swigs → swigs          taint → taint
     tan → ant              tang → want            tank → kant
     tea → net              teem → meet            tet → tet
     tia → nit              tidy → quit            tim → mit
     time → emit            timer → remit          ting → wait
     tip → pit              tips → spit            tit → tit
     tog → wot              tool → foot            toot → toot
     top → pot              tops → spot            tor → rot
     tort → trot            tot → tot              tow → got
     trevor → robert        trot → tort            urea → nerd
     via → nib              vow → gob              wads → sung
     waifs → sling          wait → ting            waiting → waiting
     waits → sting          wang → wang            want → tang
     wig → wig              wigs → swig            wot → tog
     wow → gog

    So of all of these, footstool (··–· ––– ––– – ··· – ––– ––– ·–··) is the longest English word that is a palindrome in CW. Here is how it sounds at 18wpm: forwards, backwards.

  • FIXME: not quite right morse tree

    It’s not quite right yet, but I’ve never worked with Graphviz before this evening. Strongly influenced by the graphic on learnmorsecode.com. The wikipedia one is the wrong way round.

    Source: morse.gv

  • K3NG Arduino Keyer

    I’m pretty amazed that the above image is even vaguely readable. It’s Hellschreiber, generated by Anthony K3NG Good’s Arduino CW Keyer. What you’re seeing, though, is Hellschreiber from the keyer’s sidetone generator being fed through a piezo glued to a paper cup (and not just any paper cup) being picked up by Fldigi on my laptop’s microphone. This isn’t what you’d call a quality signal path, and it’s a tribute to the mode’s robustness that it can be made out at all.

    Anthony has packed an absurd amount into this keyer. There isn’t enough memory on a stock 32K Arduino for all the features to be enabled. I’m planning to use it as a CW keyer alongside Fldigi as the decoder. Despite all the features that can be built in, I’d just be using it as a serial to Morse converter, with perhaps a couple of memory keys for calling CQ and the like.

    I do have a slight problem with it while it’s breadboarded, though. The wiring’s so sensitive that the control circuit triggers if I put my hand near it, let alone touch the command button. I’ll have to do something about that. I can’t breadboard for toffee.

  • Cheapo CW key

    Cheapo morse key (an Ameco K-4, $20 from Ham Radio Outlet) mounted on a $4 piece of wooden moulding.