HELP i have a problem with the nixie clock it all most workes but the number one will not display on any of the tubes all the other numbers are ok im useing the correct voltage 12v A/C any body got any ideas? 
Hi,
Unfortunately I do not have a schematic of the tubes but lookig at the schematic for the board it kind of sounds like a cold or incomplete solder joint going from the PIC (IC1) You check for continuity between the pins from IC1 to R14-R23 then from R14-R23 to the base of T6-T15 then from the collector of T6-T15 to the header pins.
Also check all of the emitter pins on T6-T15 to make sure they are going to ground.
I hope this helps.
hi
still having the same problem i have double checked my work but i do not have the required
skills to check component could the support team at velleman give me some advice on what could be the problem ? . if it was just one tube then it could be a poor solder joint but as it is all the tube not displaying the number one could it be a faulty I.C ?
PS thanks for your help wrong way
Most likely the transistor that is responsible for displaying the ‘1’, T14, is defective.
HI
problem now solved it was a faulty transistor T14 had to change it for T15 as i have no spares any chance you could send me a replacement got no zero now . but problem solved
very pleased 
Please supply an address so we can send a spare transistor.