Talk:Tap code

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Origin?

If it was featured in a 1941 book, then it was reinvented or something in 1965.
—wwoods 18:21, 18 March 2007 (UTC)[reply]

David Kahn's classic "The Codebreakers" mentions Cyrillic-based versions of this cipher as being used in Czarist jails, so obviously it was not invented for the first time in 1965. Maybe its use among American POWs in Vietnam first happened in 1965... AnonMoos (talk) 20:46, 31 January 2008 (UTC)[reply]

I've reworked the article to indicate the above. Wasted Time R (talk) 12:51, 8 April 2008 (UTC)[reply]

Other tap codes

[moved here from a user talk page]

I understand your motivation for removing the 'optimization' section. But I have a different view on the subject "tap code": A tap code for me is a way to communicate by tapping with a finger on a table. When I think about a tap code, I am not interested in war, prison, military or in fact history at all. All I want to know is, which tap codes are conceivable, what their advantages and disadvantages are, and how they work. In your view, there exists one single tap code, in analogy to the one single Morse code. But the tap code is not called Smitty code or named after anybody at all. So the name "tap code" refers to the specific means this code is transported, i.e. by tapping. As interesting as the use of tap codes throughout history is, it is not everything to say about them. And in my view, Wikipedia should reflect all views on a subject, not only the historical one.

The motivation for simply filling the alphabet in a 5x5 square, is, because it is easy to teach it to a fellow prisoner. But what if someone wants to use a tap code outside of prison? What if he or she has time to learn a more sophisticated code? The efficiency is the main motivation then, and it is a nice exercise to think about tap codes that work and are more efficient than the standard one. 129.69.65.164 (talk) 13:33, 18 April 2008 (UTC)[reply]

What you are thinking about is great from an intellectual viewpoint, but is not allowed in Wikipedia per its WP:No original research rule. Wasted Time R (talk) 14:36, 18 April 2008 (UTC)[reply]

Yes...how dare anyone try to make Wikipedia credible and consistent? The Automobile entry should be entirely about the Model T, and the Equation entry can't cover anything but the Quadratric equation, else it's original research, according to Wasted Time R! Sheesh...and some people wonder why Wikipedia remains a joke! 68.83.72.162 (talk) 13:57, 7 June 2008 (UTC)[reply]

Your analogies aren't apt. Wasted Time R (talk) 14:05, 8 December 2008 (UTC)[reply]

Ciphers which use a Straddling checkerboard (like the Russian "SNEGOPAD" cipher discussed in Kahn's Codebreakers) are a way of encoding alphabets into two numbers with greater efficiency than a simple square matrix, but I don't know that they've ever been used with tap codes... AnonMoos (talk) 13:55, 8 December 2008 (UTC)[reply]

The prison context tap code has to be simple to teach, simple to learn, simple to use. It's expected that the prison guard population doesn't have any codebreakers among them. Wasted Time R (talk) 14:05, 8 December 2008 (UTC)[reply]

The principle use I see for the tap code today is when people are trapped under collapsed buildings. It can almost be taught via tapping. In such a case, the goal is simplicity, not efficiency. But the grid ought to omit Z, not the K; a simple alphabet in the grid. Slavish adherence to Roman practice is sort of silly. Friendly Person (talk) 18:50, 28 June 2012 (UTC)[reply]

If you want efficiency, adapt the tap code to put ETAOINS etc. first in the upper left area of the grid. Friendly Person (talk) 18:50, 28 June 2012 (UTC)[reply]

Trivia section?

I wonder if it's worth mentioning that (at least the MSX version of) Metal Gear 2: Solid Snake features the same tap codes with numbers added to it in several occasions (you have to find out at least two radio frequencies with them). They are even included in the manual: http://www.msxnet.org/gtinter/Operate2.htm —Preceding unsigned comment added by Rautasydan (talk • contribs) 18:26, 3 May 2009 (UTC)[reply]

You can mention it, but not in a trivia section (which are bad); work it in to the main text. Wasted Time R (talk) 18:32, 3 May 2009 (UTC)[reply]

Be it in a trivia section or not, this kind of information is trivia itself, irrelevant to the real life usage of the code, thus it must not be included. It is enough to have it here in the discussion. Regards! Alchaemist (talk) 01:52, 3 July 2010 (UTC)[reply]

I see a lot of articles with a section "<Subject of Article> in Popular Culture. Is that bad? Friendly Person (talk) 18:42, 28 June 2012 (UTC)[reply]

Convert this to a table

The Cyrillic version needs to be added as a separate table.

However, the original source material does not have it in an HTML table so someone more skilled needs to do it.

The code was relatively straightforward: letters of the Russian alphabet were laid out in five rows of six letters:

А Б В Г Д Е/Ё
Ж З И К Л М
Н О П Р С Т
У Ф Х Ц Ч Ш
Щ Ъ Ы Э Ю Я

Each letter was then designated by a pair of taps, the first signifying the row, the second the position in the row:

1,1 1,2 1,3 1,4 1,5 1,6
2,1 2,2 2,3 2,4 2,5 2,6
3,1 3,2 3,3 3,4 3,5 3,6
4,1 4,2 4,3 4,4 4,5 4,6
5,1 5,2 5,3 5,4 5,5 5,6

Even those who had not read about the code or learned it from others sometimes figured it out, as there were standard methods of teaching it.

Those who knew it would sometimes tap out the alphabet, over and over again, together with one or two simple questions, in the hope that the unseen person on the other side of the wall would catch on.

Eyreland (talk) 00:06, 9 August 2014 (UTC)[reply]

Not sure that can be the truly original form of the tap code, since it reflects a form of the Russian Cyrillic alphabet after the 1918 reforms, and so would appear not to be suitable for use in the Tsarist era... AnonMoos (talk) 14:38, 10 August 2014 (UTC)[reply]

Oops, I looked at David Kahn's "The Codebreakers" for the first time in a number of years, and he says that in the Tsarist jails, a form of tap code based on a 6x6 square "to accommodate the 35 letters of the old Russian alphabet" existed, but more often a rectangle of "five across and six down" was used. The 30-letter rectangle would have used a streamlined form of the Russian alphabet similar in some ways to that of the 1918 spelling reform, but not necessarily identical to it... AnonMoos (talk) 05:36, 15 July 2022 (UTC)[reply]

Typos

"For example, if you hear four knocks, you can think A...F...L...Q. Then after the pause, you hear three knocks and think Q...R...S to arrive at the letter S."

Rather than "A...F...L...Q" shouldn't it be Q...R...S...T...U?

I don't know this code so it might just be that I don't understand.

The first four knock indicates the row (A F L Q V), so you establish the Q row. Then after a pause, three knocks indicates which column of the Q-row (Q R S T U), for S. row 4, column 3 = S. ~ Röbin Liönheart (talk) 15:39, 28 May 2018 (UTC)[reply]

Jack London refernce

In the early part of The Star Rover by London, prisoners communicate by an constantly changing version of a tap code.

From chapter 5:

The matter was easy of explanation. I had known, as every prisoner in San Quentin knew, that the two men in solitary were Ed Morrell and Jake Oppenheimer. And I knew that these were the two men who tapped knuckle-talk to each other and were punished for so doing.
That the code they used was simple I had not the slightest doubt, yet I devoted many hours to a vain effort to work it out. Heaven knows—it had to be simple, yet I could not make head nor tail of it. And simple it proved to be, when I learned it; and simplest of all proved the trick they employed which had so baffled me. Not only each day did they change the point in the alphabet where the code initialled, but they changed it every conversation, and, often, in the midst of a conversation.
Thus, there came a day when I caught the code at the right initial, listened to two clear sentences of conversation, and, the next time they talked, failed to understand a word. But that first time!

— Preceding unsigned comment added by 165.225.48.113 (talk) 02:43, 26 June 2019 (UTC)[reply]

Error in Article.

The article says, "Morse code is harder to send by tapping or banging because it requires the ability to create two clearly distinguishable forms of tap, such as varying the pitch or volume." I am a amateur radio operator, Morse code has nothing to do with pitch or volume. It is timing of tone and no tone. See https://en.wikipedia.org/wiki/Morse_code "Representation, timing, and speeds".
International Morse code is composed of five elements:
1. dit ( ▄ ): is one time unit long
2. dah ( ▄▄▄ ): three time units long
3. inter-element gap between the dits and dahs within a character: one dot duration or one unit long
4. short gap (between letters): three time units long
5. medium gap (between words): seven time units long.

Revised sentance, "Morse code is harder to send by tapping or banging because Morse code is time based on signal present or not present."

Changed article on 2-jul-2024.

Jchaney44145 (talk) 21:51, 1 July 2024 (UTC)[reply]

"tap tap tap BANG BANG BANG tap tap tap" and someone tapping two different objects against a wall could still be decoded as Morse. I think they're useful examples, for setting up the context of the tap code being more practical when you don't have two different-sounding objects, or have to keep quiet. Belbury (talk) 15:18, 2 July 2024 (UTC)[reply]

Morse code sounds like this, https://www.arrl.org/5-wpm-code-archive. It is one tone and the timing matters. 2603:6011:9000:186:E5D9:5F76:A53D:E70F (talk) 03:23, 5 July 2024 (UTC)[reply]

Sources about US prisoners of war in Vietnam explicitly refer to the use of two-"tone" taps and thumps to send Morse code, and how this was superseded by the tap code. I've added Jeremiah Denton's memoir as a reference. Belbury (talk) 09:14, 5 July 2024 (UTC)[reply]

I understand that you have read about Morse code. I can tell you that I have sent and received it myself and understand how it works. What is your experience level? 2603:6011:9000:186:F80E:8651:6237:A4BE (talk) 12:28, 6 July 2024 (UTC)[reply]

Thanks, I understand what Morse code is. Do you have any concerns about the current wording of the article? Belbury (talk) 12:46, 6 July 2024 (UTC)[reply]

Let’s agree with this edit.

”By comparison, Morse code being time based, is harder to send by tapping or banging. Its short and long signals can be improvised as taps and thumps, or short and long whistles or scraping sounds, but tap codes are simpler to learn and can be used in a wider variety of situations.”

I am not saying that others have not improvised sending Morse code using other methods. All I am looking for is to have this article convey correct information about Morse code. I have the experience, do you? 2603:6011:9000:186:F80E:8651:6237:A4BE (talk) 12:48, 6 July 2024 (UTC)[reply]

What do you see as incorrect here, what are you suggesting should be changed? Belbury (talk) 12:56, 6 July 2024 (UTC)[reply]

Change “ By comparison, despite its messages being shorter, Morse code is harder to send by tapping or banging.”

to “By comparison, Morse code being time based, is harder to send by tapping or banging.”

This would be more accurate. 2603:6011:9000:186:F80E:8651:6237:A4BE (talk) 13:06, 6 July 2024 (UTC)[reply]

"Time based" isn't a very clear explanation, but regardless I don't see why that would make it harder to send. Denton's "a prisoner might tap once on the wall for a dot and thump with his fist for a dash" seems no more difficult than the same prisoner whistling or scraping to send monotone morse.

Do you think it's incorrect to say that Morse code messages are shorter than tap code messages? Belbury (talk) 13:17, 6 July 2024 (UTC)[reply]

Wow, you are such the knowledgeable expert on this topic. I am glad you know more about Morse code than me.

I was just wanting to correct mistakes in the article.

--. -... 2603:6011:9000:186:F80E:8651:6237:A4BE (talk) 13:28, 6 July 2024 (UTC)[reply]

Belbury, google vband and try to get above 15 WPM. Thank you.

https://hamradio.solutions/vband/ 2603:6011:9000:186:F80E:8651:6237:A4BE (talk) 13:52, 6 July 2024 (UTC)[reply]

No matter how great Morse code is in some contexts, prisoners do not seem to have found it to be as convenient or useful as tap code in most cases. For tap code, all you need is your fist and a wall, while for Morse code, you need something else in addition, and that something else could then be taken away by the jailers, or if the something else makes a louder noise than your fist when it hits the wall, then it could cause the jailers to become suspicious, etc. etc... AnonMoos (talk) 18:48, 7 July 2024 (UTC)[reply]