Wednesday, June 13th, 2007 12:30 am
Minor rant: You can't send morse code by tapping random objects, dammit.

Morse uses beeps of different lengths. If you can't send a dit that is distinct from a dah, it just isn't going to work. For example, R is di-dah-di. It might be tempting to think you could fudge that as tap-tap-(pause)-tap, but that doesn't work. You just sent 'ie' (di-di di) instead. Spacing is used to denote letter, word and sentence boundaries only. You might as well try to speak English without any consonants.

I know it's a very convenient plot tool to have people communicating between locked rooms by hitting a pipe with a wrench. But the only message they can send is "I'm hitting a pipe with a wrench!" Please, find a better solution.
Wednesday, June 13th, 2007 08:17 am (UTC)
Except for maybe SOS, which even in taps and pauses has become sort of a universal "o shi--help please" symbol. Even if it's not proper Morse code. :)
Wednesday, June 13th, 2007 08:24 am (UTC)
Loud and soft taps?
Wednesday, June 13th, 2007 11:22 am (UTC)
What if you had spaces of two different durations? One to denote boundaries, one to denote dah.
Wednesday, June 13th, 2007 11:53 am (UTC)
Or two different tapping utensils - wrench and finger, for example.

It isn't optimal and it would be harder to interpret, but there are many ways of differentiating between patterns of sound without being able to alter the length of the sound being made. It might not strictly be Morse code, but it could, in theory, work, and basing it on Morse is as sensible as basing it on anything else...
Wednesday, June 13th, 2007 05:07 pm (UTC)
Morse already has different pause duration. The pauses between letters, words and sentences all get longer.

Obviously it would be possible to create a tap-based code. But it wouldn't be Morse, and no one would understand it. As a plot element, you'd have to previously establish that the characters had learned such a thing.
Wednesday, June 13th, 2007 11:53 am (UTC)
Although if you have a wrench you might just want to bash the lock in...
Wednesday, June 13th, 2007 01:46 pm (UTC)
I confess my non-critical mind has always reacted differently--"They always represent morse code by tapping on an object. I wonder what the standard means of differentation between dits and dahs is. Maybe they do it with duration, but not as long as the gaps between words? Huh I'll have to ask--Oh, here comes the guard, he's gonna get caught! oh, no, he's just having a cigarette..."
Wednesday, June 13th, 2007 05:09 pm (UTC)
Yeah, I always wondered that, too, but not knowing enough about Morse code myself, I just accepted it.

You *could* simply represent each beep by *two* taps. Tap tap = dit, tap pause tap = dah.
Wednesday, June 13th, 2007 08:00 pm (UTC)
I can't possibly imagine what would be simple about getting the timing consistent enough for that to be reliable unless you were going to take a very long time to send messages so that you were definitely using time durations that were obviously short, long, longer or longest.
ivy: (polite raven)
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Wednesday, June 13th, 2007 03:10 pm (UTC)
What about tap for . and scrape for - ? That's how I would do it, and I'd think both should be audible.
Wednesday, June 13th, 2007 05:08 pm (UTC)
That just might work. I should brush up on my Morse and try that someday. Could be a fun little youtube video...
Wednesday, June 13th, 2007 03:43 pm (UTC)
I always figured it was a matter of timing. If you have good timing, you set a beat and then apply half-steps for the long beat, normal beats for the short. Just like over telegraph lines.

Of course, if you have lousy timing, you'll never figure out which are the long and which are the short, which is why some people can do it and others can't.
Wednesday, June 13th, 2007 09:09 pm (UTC)
There's a real-life horror story involving morse code, that now I'm just confused about.

When the Missouri was sunk in the Pearl harbor attacks, many watertight chambers still had guys alive inside, for as long as several days until they suffocated.

According to the version of the story that I heard, these poor doomed souls were able to communicate with people up above with morse code, tapping on the metal of the ship. And people up top were able to talk back at them.

I don't think the different between a pause and a dash is a deal-killer here, you just have to take long enough in your pauses to be able to tell them from a dash. I'm sure it helps to already have one's own rythm well established... I don't think it would work if you'd never done morse code before, and were trying to use a codebook for the first time.

Oh, and the reason it's a horror story, is because command at the time decided that resources were better spent on the surface, and not expensive rescues underwater.
Wednesday, June 13th, 2007 09:11 pm (UTC)
Of course, they could always use the Tap Code (http://en.wikipedia.org/wiki/Tap_Code).