[Dekatron]

Wal,

You can hook it up to a constant current source (CCS) or simply connect it in series with a digital multimeter, some resistors of the correct value and a small battery to check it. I know I wrote about it somewhere earlier in this forum but I can't seem to find it right now. Just calculate the reistors according to the current you need to have in the circuit and hook it up, you can use a potentiometer in series with the circuit to change the current somewhat to see how it behaves. Just be carefull not to overload it.