The Bolt Industries Vacuum Florescent Display Layer Clock soldering kit from Kickstarter. This kit includes everything you need to build your clock, including your choice of IV-3A or IV-6 VFD tubes. Other optional displays include the Binary Coded Decimal LED display, 7 segment LED Display and Hewlett Packard’s HDSP series displays.

If you’ve ever gone looking for a nixie or vacuum florescent display clock on the internet, you’ve probably noticed that the number of pictures of these clocks far outnumbers the number of actual clocks and open source designs that are available. This clock is designed to change that with an open source design that is compatible with a wide variety of vintage and modern displays, including vacuum florescent display tubes and modern LED displays.

Available in black or green. Includes everything needed to build your clock except tools. Requires a micro USB power supply. This is an advanced soldering kit due to the large number of components. Assembly instructions as well as all open source design files can be found at: www.boltind.com

All VFD tubes were sourced from Ukraine.

Interchangeable layers:

Bottom Layer:

The bottom layer is where the timekeeping happens, and it outputs a 4 bit binary coded decimal format that can be used directly with a display that uses a 4 bit BCD input. This layer is available in a TTL (Transistor – Transistor Logic) edition that uses only 7400 and 4000 series integrated circuits, or a Raspberry Pi Pico based version that runs on software.

Middle Layer: The Middle layer is a binary coded decimal to 7 segment decoder. This layer can alternatively be substituted with an output display that can use the BCD format directly.

Top Layer: The top layer is a 7 segment output display. Your choice of VFD Display is included with this kit.

IV-3A VFD tubes have a smaller grid in front of the digit, so the digits look sharper that the IV-6 tube. They also frequently have a beautiful oxidized blue color. IV-6 tubes are slightly larger.