“Glowing retro tubes made in the Soviet Union? 80’s electro-style? Sign me up! (or sign us up comrade?)
Many of you probably know how these things go: you start with making a nixie clock and you end up with a self full of Soviet tube clocks! That’s what happened to me as well: while researching nixie tubes I found out about VFDs, the display technology that replaced nixies. At that time I knew what my next project would be. Unlike with nixies, I’m old enough to remember this bright cyan segmented displays being everywhere, from cars to Hi-Fi sound systems, back when I was a kid. Nostalgia aside, this retro yet futuristic contradictory vibe that they have is appealing to me. VFDs it was then!
Being an amateur in electronics and completely self taught, I try to make every new project be a step forward from the last. My nixie clock was made on a perfboard utilizing an Arduino Mega and ready made power supplies (if you are interested in checking it out here is the link: https://create.arduino.cc/projecthub/deathorion/diy-nixie-clock-on-perfboard-7c47d1?ref=search&ref_id=perfboard%20nixie%20clock&offset=0 )
So, for the VFD clock I decided to design my own PCBs and power supplies. Luckily, there are a lot of free PCB designing tools out there and many services that can cheaply built your PCBs. I used EasyEDA for the design which is indeed easy to use and free.
I chose the IV-22 VFD tubes because this time I wanted to use a different form factor than the IN-14 nixie tubes that I used on my previous clock. In case you are interested, you can get nixie tubes in the IV-22 form factor, they are called IN-12. Of course they are not interchangeable because they work in a completely different way but the tube has pretty much the same shape and size. All these types of tubes are not manufactured anymore but are available to buy online (ebay mostly) either used or unused from old stocks - usually referred to as NOS (New-Old Stock).
Features:
The clock has the following features implemented:
- Time display of course, both in 24 and 12 hour format, with blinking colon and am/pm indicator
- Accurate time keeping and battery to keep the time when the power is off
- Room temperature and humidity display
- RGB LED backlight on the tubes, with five different color effects
- Light sensor and automatic dimming of the tubes and LEDs depending on the light in the room
- Four buttons which can control the following:
- set the time
- switch modes (12hour, 24hour, temperature & humidity periodically, temperature & humidity only)
- circle through the LED color effects
- turn the LEDs on and off
- Less than 500mAmps power consumption so you can power it even from computer USB ports
- Overvoltage protection
- Overcurrent protection
- ESD (Electrostatic discharge) protection
- easy access for repairs
I’m also planing to implement the following features in the firmware:
- Routine that turns the tubes and LEDs off at night when there is no light in the room to save power and increase their lifetime
- Save the settings to EEPROM in order to keep them after resets and power cutoffs
- Startup routine when you plug it in so you can see that everything is working (and to look cool)”