This is a simple 0-9 counter utilising a nixie tube. I have conceived the idea for this project when I bought some ИН-14 nixie tube from eBay from Ukraine. I had bought a nixie clock kit from eBay (surprise surprise) a few years back, it didn't work. I salvage the К155ИД1 IC. The job of the IC is to convert BCD to decimal and it has high-voltage outputs. Instead of using the К155ИД1 you can use the 74141 IC to my belief they are exactly the same (except one has not been affectd by capitalism), the 74141 datasheet is included in the downloads section as I can't locate the К155ИД1 datasheet. This works by using the NE555 as an astable oscillator, the clock goes into a selector switch, it selects the method of advancing the display. The switch positions are as follows: 1, AUTOMATIC; 2, SEMI AUTOMATIC; & 3, MANUAL. As you could probably guess automatic automatically advances the display, semi automatic advances the display as long as the button is held down and manual advances the display on the press of the button.

  • К155ИД1
  • DM7490
  • NE555
  • Switch, 3POS Rotary
  • Switch, Push button
  • Resistor, 4.7k, 1/4W, Carbon Film
  • Resistor, 47k, 1/4W, Carbon Composition
  • Resistor, 100k, 1/4W, Metal Film
  • Capacitor, 4.7uF, 16V, Tantalum
  • Capacitor, 10nF, 50V, Ceramic
  • Capcitor, 100nF, 50V, Ceramic
  • Valve, ИН-14

Schematic

Top copper layout

Bottom copper layout

Silkscreen layout

Solder mask layout

PCB layout