New Old Nixie Clocks

These beautiful Nixie clocks deserve to have little space on my blog. They are made from Russian tubes bought on ebay. Timekeeping is "extremely accurate" as it is stated on DS3231 RTC datasheet. DS3231 are temperature compensated RTC's, so there's no need to adjust them between clock shifting each year.
Two types of tubes are used: small but more beautiful IN-14 and larger IN-16 tubes. Both are relatively new NOS, as you can see on pic below they are dated 1982-1989. That's not very old.


 You can see TLC5941 led driver on top board. These chip drive four RGB leds placed under each tube. And also, chip is used to regulate brightness of the tubes. RGB leds can be set to change colors, you can get any color in spectra by mixing these 3 basic colors. Leds in action are on following pics:

Clock can show time/seconds/date/temperature. Temperature shown is little above room temperature, due to voltage booster self-heating. This temperature is measured by RTC chip and is used to compensate oscillator ccording to temp. It is known that quartz oscillators run faster on high temperature.

Toggling between display modes:

Bottom board is the same for both clocks. On board there are: ATmega328 controller, High voltage tube driver ( high voltage BCD decoder) old and Made in USSR, voltage booster with mosfet transistor, DS3231 RTC with battery, 12 MHz quartz and +5V regulator.




Following tester is to detect malfunctioning K155ID Nixie driver and tubes. I personally receiver few dead chips and tubes from ebay. From 5 pcs 3 were dead. After assembling the clock it was not easy to detect bad chip. With this simple device it's easy.
So anyone interesting in building Nixie clocks should get one!


It's binary controlled: 1001b = 9d.

Comments

  1. GOOD ! Welcome ! http://www.petrofflab.ru/

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  2. Thanks!
    Your blog is excellent! I love your Nixie stuff! Keep up your work!

    ReplyDelete

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