Dots and Dashes… on a Roll!

Morse code was once a staple of the communications industry, but with advancing technology it has become relegated almost exclusively to movies and a niche group of ham radio operators. [Jan] has created a device which might not put a stop to this trend, but will at least educate children on the basics of how Morse code works by visually displaying Morse code as it’s generated.

The setup is fairly simple. An old momentary switch (which could easily be used in an actual Morse code setup) activates two pieces of circuitry. The first is a 555 timer circuit that creates an audible tone when the switch is pressed so the user can hear exactly what an operator would hear when decoding a real Morse code message.

The second piece of circuitry is where the real genius lies: a continuously spinning roll of glow-in-the-dark tape is placed in front of a white LED. When the switch is pressed, the LED turns on, which produces dots and dashes on the roll of tape as it passes by. This eliminates the need for rolls of paper or a more complicated moving pen/pencil setup to draw on the paper which might also be less child-proof.

While [Jan] built this as a toy, the children who used it thoroughly enjoyed it! They even decoded some Morse code messages and used the device to practice on it. After a while they’ll easily be able to master the Morse code trainer!

26 thoughts on “Dots and Dashes… on a Roll!”

1. netbeard says:

Coolest Morse code related hack I’ve seen was the binary search tree.

You can traverse the tree to determine each character.

1. vonskippy says:

So 14 dots equal a “e” and 6 dashes equal a “t” – wow, no wonder it takes forever to send a message in morse code.

1. Me says:

Maybe you are joking? Woosh!

You aren’t meant to count the dots. Travel down a dotted branch you get one dit. Travel down a dashed line you get one dah. e = 1 dit, t = 1 dah

2. Huh? ‘e’ is the shorted character is Morse: just a dot. And ‘t’ is the same, just a dash. It does not “take forever”. I personally know ham radio operators who can copy Morse at 20 English words per minute, and I can copy at ten. Of course, not everything is spelled out; there are abbreviations for lots of things, including “and” (the ampersand is a character).

But that’s alright. You go ahead and think we’re dinosaurs.

2. oddware says:

This is great!
Thanks for sharing.

2. Me says:

I am very slowly learning Morse myself. To me it’s not the old-schoolness or any particular afinity to the sound (although there are many hams who like Morse for those reasons). I am interested because of the maker opportunities!

Building a voice transmitter that is stable and clean enough that it can be used at high enough powers to travel long distance without getting negative regulatory attention is a challenge. RasPi PWM pins and 2 transistor FM bugs don’t have a chance!

CW (the mode used for Morse) transmitters are much easier (beginner friendly). Also less power is needed. Actually, QRSS (really really slow Morse CW) has been known to cross the Atlantic with mere milliwatts of power! CW transmitters can be built with as little as a single transistor plus a handful of passive components.

At the slow rate I am learning Morse I will probably be building voice transmitters before I feel comfortable enough at it to go on the air with the CW transmitter I have already built. Oh well… I will keep trying!

3. Ty Tower says:

For the information af all it is a language that can be learnt in three months and is never forgotten . learn Morse, French and Spanish and you have most of the world covered if English is your first.

1. Whatnot says:

Really? What’s the point of morse in this day and age?,Apart from personal fun with some geeks friends

4. NullPointer says:

.- .– . … — — .

1. chiefcrash says:

.- –. -. ..–.. .- –. -. ..–.. …. .. …. ..

5. echodelta says:

In WW2 pilots could text while shooting with a key on the knee. Everyone had to learn. If taught in grade school today we could be free of qwerty in a decade. And kids could whoop ass over most seasoned hams.
The biggest problem with this hack is Morse is listening not looking, telegraph operators found that out in the mid nineteenth century. The graphing of received message went out way back then.

1. Blue Footed Booby says:

Heard something on NPR about a guy who was captured during ‘Nam. He’d compose poetry in his head to pass the time and keep his mind sharp, then perform them for the other inmates via morse code through the walls. He finally published them in written form a few years back in a book called Taps on the Wall.

Just thought I’d share.

2. Whatnot says:

Get rid if qwerty and replace it with morse? You can tell they legalized weed I guess.

6. genki says:

Would an UV LED leave a brighter trail on that roll? I do know some materials glowed brighter with UV light rather than white light.

1. Foobar Bazbot says:

Possibly, it all depends on the relative intensity of the UV LED.

Typical white LEDs are a blue LED with a phosphor coating which converts some fraction of the blue light to longer wavelengths, creating a broad yellow band, which together with the remaining blue light makes a visually white color, with a dearth of deep red and green wavelengths. The wavelength of the unconverted blue fraction is short enough to work practically as well as the ~400nm of common “UV” LEDs (most are rather visible) for common GITD phosphors, but the fraction converted to yellow light is useless. So given the same photon density, deep blue or UV LED beats white LED.

But even more, the lack of glare from a UV LED would be a great improvement, even if the UV LED were driven more gently to achieve the same glow brightness.

2. yes uv led and shurtech tape makes awesome play things!

7. Hirudinea says:

If you replace the LED with a high powered laser (covered of course) and the glowing roll with a roll of heat sensitive tape you would keep a record of your morse.

1. RunnerPack says:

Lasers are cool, and all, but all you’d need for making a mark on thermal paper is a power resistor or a small piece of nichrome wire.

1. Hirudinea says:

But what about the heat up, cool down time? And of course lasers ARE cool.

1. RunnerPack says:

Well, they manage it in receipt printers and the like, so it has to be doable.
I see two basic options:
1) Use a (low thermal mass) heater capable of much more heat than necessary, then “PWM” it down to the average temperature you need.
2) Mount an “always on” heater on a solenoid.

8. j0z0r says:

Thanks for this, I was looking for a hack to show off my glow in the dark duct tape. I was thinking a laser POV tic tac toe game, but this is better

9. dhavenith says:

Neat! It appears to be quite visible in daylight conditions as well. Never knew that glow in the dark tape would work that well.

The idea of using GitD tape on a roll opens other opportunities. Add 7 more leds (or 15) and you have a simple “persistence of vision”-marquee. OK, maybe getting a bit carried away while [Jan] explicitly mentions his dislike for overly complex builds.

1. Never mind SENDING (which is always easier than receiving ), this technique (especially in the drum was turned thru’ 90 degrees) could suit receiving!

Mmm-multiple LEDs could even suit character “printing” under the likes of multitone Hellschrieber. See a PICAXE micro approach using Spectran decoding =>http://www.picaxe.orconhosting.net.nz/smthell.htm 73’s de ZL2APS

10. cyberteque says:

for all those who think Morse code is for dinosaurs, when you’re trapped in that submarine and a rescue diver is belting away on the hull you wont know if he’s saying “We’ll have you out in time for supper” or “Sorry guys, you’re screwed”

If you got to a sign shop that cuts out vinyl lettering, they should be able to sell you some of the glow in the dark stock, it comes on a roll about 30 – 50cm wide.

great thing to do is get a big piece, put some random objects on it, keys, tools, whatever, and hit it with a flash gun, then take the stuff away.

Works with negatives and transparencies as well

11. Mr Name Required says:

Very nice modern version, it looks cool.
Here’s a project to build a simple Morse code Recorder from a 1947 australian Hobbies magazine. It uses hand-cranked paper tape that is dipped in a postassium iodide solution. The weak current passing through two close wires in the ‘recording head’ turns the paper brown at that point:

12. Bill Ripley KY5Q says:

When I learned Morse Code for my Novice license, I wrote down the alphabet on a shirt cardboard (remember them) and started at the top saying out loud “A dit dah, B dah dit dit dit, etc in an pattern of a, ab, abc, abcd, abcde, etc all the way through, and then starting at z, zy, zyx, etc (actually included numbers but it is easier to describe). The good news is that on the night before the test, i learned Morse Code well enough to pass a 5 wpm test the next day. The bad news is that I set myself up counting dits and dahs, and referring to “crutches” like “F” as “dit dit dah dit” as the music from “Cream” etc. That is a hard habit to break, and for years I was stuck at 20 wpm because I would trip over the crutches. Once I learned to copy without a crutch, by listening as you would French or Spanish, I was able to go to 40 wpm plus, and the increase came easily. Its just a different way of thinking about how to learn. 73 Bill KY5Q