The ChronodeVFD is a personal project I’ve been working on for a couple of months. It’s a wristwatch built around the IVL2-7/5 VFD display tube. I originally purchased a few of these tubes to build a standard desk clock, but after playing around with them, I realized I could probably build a wristwatch too. The tube has a number of features which make it more suited than most Soviet-surplus VFDs for this purpose.
nominal 60mA filament current @ 2.4V, but still works with ~35mA @ 1.2V.
It’s small — only 1.25 x 2.25″
It’s flat, as opposed to the round tubes like the IV-18, which would be much clunkier in a watch design.
can operate from a relatively low grid voltage of 12-13V (up to 24V)
pulls only about 2.5mA/segment from the grid rail @ 12.5V. (“8″ = 20mA)
One other feature that I like about this device is that unlike nearly every other VFD tube, the IVL2-7/5 has no opaque or diffuse backing behind the digits. It’s completely transparent front to back, which means that if you put it on top of a circuit board, you can (with a bit of backlighting) see the PCB below.
8-6-2021 (August 6, 2021) is the Snakiest day of the year and it’s also this year’s CircuitPython Day! The day highlights all things CircuitPython and Python on Hardware. See you there!
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.