Russian tri-color VFD Indicator Clock
I was drawn to the unique quality of this display. I had just built a VFD 7 segment clock, and wanted to play around some more with Vacuum fluorescent displays.
I am interested in making a clock - one which is not necessarily for telling THE time, but indicating the passing of time.
After doing the VFD clock, I found these Soviet new-old stock tri-color indicators on Ebay.
The datasheet came in Russian, so I google translated the text.
I am going to use a MAX6921 20 output VFD driver chip.
See this blog post about troubleshooting VFDs here:
This display has 3 colors: Blue, Red, and Green. There are 5 lines with 7 of each color in each line - therefore, I have 35 Blue segments, 35 Red segments, and 35 Green segments.
I have 21 addressable pins (7 of each color).
Beginning the wiring and coding. I tested the transistor circuitry to control the grids with some LEDs.
The Russian VFD has five lines of segments of colors. By switching the grids on and off I can multiplex the component.
Each Grid gets a circuit which is comprised of one TIP120 - (NPN), two 10K resistors, and an IRF9510 - (MOSFET PNP).