# Morse code by telegraph question

**URL:** <https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728>\
**Category:** Factual Questions\
**Created:** [April 29, 2009, 1:41pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728 "2009-04-29T13:41:08Z")\
**Posts on this page:** 20\
**Page:** 1

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**Author:** ![Rocketeer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rocketeer/32/4437_2.png) [@Rocketeer](https://boards.straightdope.com/u/Rocketeer)\
**Post date:** [April 29, 2009, 1:41pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/1 "2009-04-29T13:41:08Z")

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How does Morse code sent by telegraph work? If, for instance, you wanted to send “U” (dot-dot-dash), would it sound like this:

click-click-(pause)-click?

or this:

click (short pause)-click(short pause)-click (long pause)-click ? (that is, do the pauses correspond to dots and dashes?)

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**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\
**Post date:** [April 29, 2009, 1:55pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/2 "2009-04-29T13:55:15Z")

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Neither. It would be:

bzt-bzt-bzzzt

In other words, the key would be pressed down for longer to make the dash.

You can see the trace from Morse’s first telegraph message [here](http://upload.wikimedia.org/wikipedia/commons/f/f1/The_First_Telegraph.jpg).

Transmission isn’t limited to “clicks” - the signal is transmitted for as long as the key is held down.

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**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\
**Post date:** [April 29, 2009, 1:58pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/3 "2009-04-29T13:58:25Z")

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I think you have it backwards. Morse is essentially a trinary code, with pauses the same length, dots a short click, and dashes a long click. (Although now that I think about it, how do you make a “click” longer? Makes more sense with beeps.)

ETA: what **Colophon** said.

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**Author:** ![Rocketeer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rocketeer/32/4437_2.png) [@Rocketeer](https://boards.straightdope.com/u/Rocketeer)\
**Post date:** [April 29, 2009, 2:13pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/4 "2009-04-29T14:13:44Z")

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Ah, okay, I understand. I had thought that all a telegraph receiver could do was click; I didn’t realize it could “buzz”.

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**Author:** ![UncleRojelio](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unclerojelio/32/3160_2.png) [@UncleRojelio](https://boards.straightdope.com/u/UncleRojelio)\
**Post date:** [April 29, 2009, 2:44pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/5 "2009-04-29T14:44:25Z")

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> [@Rocketeer](#):
>
> Ah, okay, I understand. I had thought that all a telegraph receiver could do was click; I didn’t realize it could “buzz”.

The early telegraphy used a [sounder](http://en.wikipedia.org/wiki/Telegraph_sounder) that could only produce clicks and clacks. They also used the [American Morse code](http://en.wikipedia.org/wiki/American_morse_code) which is different than the International Morse code used today.

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**Author:** ![Kevbo](https://avatars.discourse-cdn.com/v4/letter/k/e47774/32.png) [@Kevbo](https://boards.straightdope.com/u/Kevbo)\
**Post date:** [April 29, 2009, 3:05pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/6 "2009-04-29T15:05:40Z")

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> [@UncleRojelio](#):
>
> The early telegraphy used a [sounder](http://en.wikipedia.org/wiki/Telegraph_sounder) that could only produce clicks and clacks. They also used the [American Morse code](http://en.wikipedia.org/wiki/American_morse_code) which is different than the International Morse code used today.

This is correct. The sounder has a slightly different tone when the coil energizes vs. when it releases. Click and clack is about as good as you can discribe it with words. It was not uncommon to add a plug tobacco tin to the sounder frame near the top stop screw to enhance this difference, as well as to give a different character to the sound for multiple sounders in one office, and make the sounder a bit louder.

International morse arose because undersea cables were unable to transmit the long dashes used in some American Morse characters. One polarity was used for dots, the other for dashes. The long cable lengths caused temporal distortion, so dots and dashes on such cables could not be distinguished by length.

Land line telegraphy hung on for a long time in railroad dispatching work long after telephones had replaced it in the general populace. When you need to transfer information with no alteration to a third party, (train orders) voice isn’t really any faster than morse code…you have to spell out any unusual word, and can only go as fast as the recieving operater can write or type.

So to the OP:

The letter a (dot dash) would sound like

click\_clack\_click\_\_\_clack

With only the underscores indicating elapsed time.

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**Author:** ![Keeve](https://avatars.discourse-cdn.com/v4/letter/k/f07891/32.png) [@Keeve](https://boards.straightdope.com/u/Keeve)\
**Post date:** [April 29, 2009, 3:09pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/7 "2009-04-29T15:09:28Z")

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> [@Lumpy](#):
>
> I think you have it backwards. Morse is essentially a trinary code, with pauses the same length, dots a short click, and dashes a long click.

Not trinary, but **four** -part. IIRC there were short pauses within a letter, and long pauses between letters.  
So, for example, SOS (dot dot dot dash dash dash dot dot dot) was like this:

bzt \_ bzt \_ bzt \_ \_ \_ bzzzt \_ bzzzt \_ bzzzt \_ \_ \_ bzt \_ bzt \_ bzt

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**Author:** ![Keeve](https://avatars.discourse-cdn.com/v4/letter/k/f07891/32.png) [@Keeve](https://boards.straightdope.com/u/Keeve)\
**Post date:** [April 29, 2009, 3:10pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/8 "2009-04-29T15:10:29Z")

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And that’s why, instead of adding another code for end-of-sentence, they used the word “stop”.

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<div class="post-metadata">

**Author:** ![Rocketeer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rocketeer/32/4437_2.png) [@Rocketeer](https://boards.straightdope.com/u/Rocketeer)\
**Post date:** [April 29, 2009, 3:22pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/9 "2009-04-29T15:22:38Z")

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So SOS in railroad telegraphy would be

click-clack\_click-clack\_click-clack\_\_\_\_\_\_click—clack\_click—clack\_click—clack\_\_\_\_\_\_\_click-clack\_click-clack\_click-clack?

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**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\
**Post date:** [April 29, 2009, 3:26pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/10 "2009-04-29T15:26:24Z")

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> [@Rocketeer](#):
>
> So SOS in railroad telegraphy would be
> 
> click-clack\_click-clack\_click-clack\_\_\_\_\_\_click—clack\_click—clack\_click—clack\_\_\_\_\_\_\_click-clack\_click-clack\_click-clack?

No. In your writing: click – click – click ---- clack – clack – clack ---- click – click – click.

Or what Keeve already wrote.

Why are you doubling each sound?

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<div class="post-metadata">

**Author:** ![Ximenean](https://avatars.discourse-cdn.com/v4/letter/x/aca169/32.png) [@Ximenean](https://boards.straightdope.com/u/Ximenean)\
**Post date:** [April 29, 2009, 3:26pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/11 "2009-04-29T15:26:37Z")

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People have successfully sent Morse code using effectively binary signalling devices, such as banging on pipes, and yes, the length of the pause after the sound indicates whether it’s a dot or a dash. It does introduce some ambiguity, and so requires some guesswork on the part of the decoder. A message UUU (no spaces) would sound very much like S S S (with spaces).

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**Author:** ![Acsenray](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/acsenray/32/4519_2.png) [@Acsenray](https://boards.straightdope.com/u/Acsenray)\
**Post date:** [April 29, 2009, 3:30pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/12 "2009-04-29T15:30:22Z")

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Perhaps the source of the confusion is that someone standing next to a telegraph operator would hear only the clicks. You’d have to put on the headphones to hear the actual content.

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**Author:** ![UncleRojelio](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unclerojelio/32/3160_2.png) [@UncleRojelio](https://boards.straightdope.com/u/UncleRojelio)\
**Post date:** [April 29, 2009, 3:30pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/13 "2009-04-29T15:30:25Z")

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> [@Rocketeer](#):
>
> So SOS in railroad telegraphy would be
> 
> click-clack\_click-clack\_click-clack\_\_\_\_\_\_click—clack\_click—clack\_click—clack\_\_\_\_\_\_\_click-clack\_click-clack\_click-clack?

Well, I don’t know why a railroad telegrapher would send ‘SOS’, but if for some reason he did, the American Telegraph code for ‘O’ is ‘.-.’, not ‘—’.

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**Author:** ![UncleRojelio](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unclerojelio/32/3160_2.png) [@UncleRojelio](https://boards.straightdope.com/u/UncleRojelio)\
**Post date:** [April 29, 2009, 3:31pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/14 "2009-04-29T15:31:57Z")

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> [@Exapno\_Mapcase](#):
>
> No. In your writing: click – click – click ---- clack – clack – clack ---- click – click – click.
> 
> Why are you doubling each sound?

Because the sounder has to return after every ‘click’, resulting in a ‘clack.’ You can’t have a ‘click’ without a ‘clack’ and vice-versa.

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<div class="post-metadata">

**Author:** ![UncleRojelio](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unclerojelio/32/3160_2.png) [@UncleRojelio](https://boards.straightdope.com/u/UncleRojelio)\
**Post date:** [April 29, 2009, 3:36pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/15 "2009-04-29T15:36:05Z")

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> [@acsenray](#):
>
> Perhaps the source of the confusion is that someone standing next to a telegraph operator would hear only the clicks. You’d have to put on the headphones to hear the actual content.

We are talking about a form of telegraphy used before headphones came into use. The clicks and clacks would have been coming from a mechanical device sitting out in the open. It didn’t have a headphone jack on it and didn’t generate a signal that could be heard via headphones in first place.

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**Author:** ![Acsenray](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/acsenray/32/4519_2.png) [@Acsenray](https://boards.straightdope.com/u/Acsenray)\
**Post date:** [April 29, 2009, 4:20pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/16 "2009-04-29T16:20:08Z")

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What era of telegraphy _are_ we talking about?

And are you saying that there wouldn’t be any buzzing? I seem to recall playing with old telegraph thingies that buzzed. The clicking sound was made by the operator, but that’s not what the receiver listened for.

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**Author:** ![UncleRojelio](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unclerojelio/32/3160_2.png) [@UncleRojelio](https://boards.straightdope.com/u/UncleRojelio)\
**Post date:** [April 29, 2009, 4:27pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/17 "2009-04-29T16:27:51Z")

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> [@acsenray](#):
>
> What era of telegraphy _are_ we talking about?
> 
> And are you saying that there wouldn’t be any buzzing? I seem to recall playing with old telegraph thingies that buzzed. The clicking sound was made by the operator, but that’s not what the receiver listened for.

We are talking about he era of the [Electrical Telegraph](http://en.wikipedia.org/wiki/Electrical_telegraph). The more familiar buzzing telegraphs came along when wireless was invented.

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<div class="post-metadata">

**Author:** ![Rocketeer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rocketeer/32/4437_2.png) [@Rocketeer](https://boards.straightdope.com/u/Rocketeer)\
**Post date:** [April 29, 2009, 4:55pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/18 "2009-04-29T16:55:02Z")

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> [@UncleRojelio](#):
>
> Well, I don’t know why a railroad telegrapher would send ‘SOS’, but if for some reason he did, the American Telegraph code for ‘O’ is ‘.-.’, not ‘—’.

Oops. But am I right otherwise?

And presumably with wireless telegraphy (International Morse), it’d be

ditditdit\_buzzbuzzbuzz\_ditditdit?

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<div class="post-metadata">

**Author:** ![whitetho](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whitetho/32/1059_2.png) [@whitetho](https://boards.straightdope.com/u/whitetho)\
**Post date:** [April 29, 2009, 5:04pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/19 "2009-04-29T17:04:01Z")

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> [@Rocketeer](#):
>
> So SOS in railroad telegraphy would be
> 
> click-clack\_click-clack\_click-clack\_\_\_\_\_\_click—clack\_click—clack\_click—clack\_\_\_\_\_\_\_click-clack\_click-clack\_click-clack?

Officially it’s not “SOS”, it is the Morse code distress signal, which instead of three separate letters, actually is three dots/three dashes/three dots all run together. Thus, it would be click-clack\_click-clack\_click-clack\_click—clack\_click—clack\_click—clack\_click-clack\_click-clack\_click-clack.

The distress signal is known informally as “SOS” because in _International_ Morse S is three dots and O is three dashes. However, in _American_ Morse, which an oldtime U.S. operator would use, while S is still three dots, three dashes stand for the numeral five, so, again informally, the distress signal was known as S **5** S. See, for example, the 1910 article [“S 5 S” RIVALS “C Q D” FOR WIRELESS HONORS](http://earlyradiohistory.us/1910S5S.htm).

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**Author:** ![UncleRojelio](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unclerojelio/32/3160_2.png) [@UncleRojelio](https://boards.straightdope.com/u/UncleRojelio)\
**Post date:** [April 29, 2009, 5:16pm UTC](https://boards.straightdope.com/t/morse-code-by-telegraph-question/494728/20 "2009-04-29T17:16:35Z")

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> [@Rocketeer](#):
>
> And presumably with wireless telegraphy (International Morse), it’d be
> 
> ditditdit\_buzzbuzzbuzz\_ditditdit?

If you want to say it out loud, the convention would be: di di dit dah dah dah di di dit.

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