Universal Stock Ticker

Hardware

This is a Universal Ticker. It is #2994 of about 6000 made between 1870 and 1900 (see edisonticker.com). My father tinkered with it a long time ago and it's been on the shelf since. During spring break 2012, I decided it would make a good project.

We're missing the original ink rollers, and I didn't have time to make that this time around, so I brushed on some wet sumi ink, which almost works. A few other little things are missing or off-kilter, but it's generally in workable condition.

Electricals

The obvious choice for control was an Arduino, but mine were all back at school. I did have an FTDI USB-Serial adaptor though, for another project (a different kind of printer). These chips have four rarely-used, yet handy wires - the flow control lines. These wires (DTR, DSR, RTS, CTS) can also be used for general-purpose input-output (GPIO), with DTR and RTS as outputs and DSR and CTS as inputs. Now, the FTDI Basic board doesn't break out RTS, so I had to solder a wire directly to the chip.

Of course, these signals are all low-power digital lines, not suited for directly powering the solenoids on the ticker. A computer power supply did the trick (at 12V), and few MOSFETs I found in my room proved perfect for switching.

Software

A little python script takes text and ticks it out on the ticker, just like in 1900.

This project was featured on Hack a Day, The Verge, and Engadget.

I consider this an ongoing project: I intend to keep tinkering later.

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