Trying to drive nixie tubes with 74141 chip

Projects General Guidance
1

I am trying to light one IN-16 nixie tube with a (Soviet) 74141 chip. As such, I have made the simplest setup possible:

I am using the arduino's +5 VDC for Vcc on the IC

Power for tubes is supplied from a dedicated supply (170 VDC)

33 Kohm resistor on IN-16 anode

Using the arduino's ground socket as a common ground for chip's ground and power supply ground

Using pins 2,3,4,5 on the arduino as inputs a,b,c,d

I have verified that each numeral works separately

This (I thought) should make it easy to begin experiments. But for some reason, when power is supplied more than one (possibly all of them, it's hard to tell) digits are lit.

Just to start with I made some code that just switched all the inputs to LOW. When running it, all the digits still light up, even though only one cathode should be letting current through.

I have verified that setting the output pins low/high does actually give 0.002/5.015 V, respectively.

Anyone know what is going on? I thought this would be easy.

2

Post your code & schematic, sounds pretty straightforward, but who knows.
http://www.neonixie.com/ic/
Sure doesn't seem like you could get all outputs on at once.

3

Thought occurs - are you switching thru all of them quickly? That might give the impression of all of them being on.