Virtual Fialka M-125 : Wheel transport mechanism. It's complex already & I've only just begun! 3 of 10 rotors in place, you can see how the clever interlaced arrangement of fingers move with each alternate rotor pulled a different direction. @cryptomuseum @tnmoc @bletchleypark

I've been looking at the Fialka M-125's movement mechanism. A complex interlocked set of fingers are pulled apart. Each finger tracks the pins on the rotor 2 up from itself which allows a tooth to engage (or not) to turn a step. Even & odd rotors turn in opposing directions!

@veritasium take a deep dive into the Enigma story. Take a look at my 3D Virtual Enigma (enigma.virtualcolossus.co.uk) and Virtual Bombe (& others) to try these machines for yourself. This Machine Made Wartime Germany (Almost) Impossible to Defeat youtu.be/JsBZOcqZerk?si=RKBa… via @YouTube

After a well earned rest, I'm starting to (probably foolishly) feel the urge to begin modelling another cipher machine. Any guesses which machine this rotor might be from? @tnmoc @bletchleypark @cryptomuseum

Recently, I've been chatting with the previous owner of Flossie (the ICT 1301 2nd gen transistor computer that's in storage @tnmoc). We've been working to get a demo program running that was used on the real machine. One mode is to print ICT1301 on paper tape, that now works!

Forgotten Polish codebreakers who helped crack Enigma uncovered tvpworld.com/94522199/bletch…

A very happy 103rd birthday Patricia Owtram. Thank you for your service @bletchleypark. Check out her extensive oral history project interview on the roll of honour : bletchleypark.org.uk/roll-of…

Update for Virtual SG-41: the numeric-only SG-41z now available at sg41.virtualcolossus.co.uk. Used for sending weather reports where the details were encoded as a set of numbers. It's very similar to the SG-41 but with a few interesting omissions which I'll be documenting soon.

On this day in 1936, Alan Turing submitted his paper "On computable numbers, with an application to the Entscheidungsproblem" where he proposed a machine which could compute any effectively calculable function, the foundations of today's computing. turingarchive.kings.cam.ac.u…

Work is progressing on the numeric only SG-41Z model of Virtual Schlüsselgerät 41 used for sending weather information. The print wheels were tricky but are done. Another difference is the SG-41Z only has 5 of the sensing arms (6 on SG-41) and 15 bars on the cage (25 on SG-41)