Ich bin der musikant mit taschenrechner in der hand.

Well, I'm a convict nerd and I couldn't avoid adding some Kraftwerk inspiration into the E-TKT. I'm a big fan of the Düsseldorf group since I was a child. At the time, I was afraid of them robots.

While I was composing for the original track in the first video, I felt that tags could relate to musical notations.

I have, in parallel to all other developments and thanks to the addition of a buzzer in the PCB,  explored some ideas and suddenly I've remembered this:

This was a cheat sheet for playing some of their music on a Casio VL-80, a small synthesizer.

Yes, you guessed right, it's all about "I'm the operator with a pocket calculator".

If you have a VL-80, you can be the operator, and apart from looking like a calculator, it is really a synthesizer.

Here is some more info about it.

Inspired by that, I researched some docs for that model and looked for the correlations between numbers and notes, and transposed that into the E-TKT. Check this cool manual for playing diverse songs into that little synth.

As the E-TKT has more characters than the VL-80, I've completed the table.

Then each label, for having specific individual characters, plays a unique melody before printing. It is cute.  ♪

And of course, there are Easter eggs... I challenge you to discover them without scanning the source code. There is a tip below, though.

♪