GI-21

17.5mm numeric tube manufactured by National Union

The GI-21 is a numeric nixie tube manufactured by National Union. It is one of the first nixie tubes ever made. The digits are hand made, and the size of the tube is relatively large. It can display 0-9. Driving the GI-21 is not very easy, because it has no anode-grid and the other digits have to be used as anodes. Along with the GI-21, National Union produced the GI-10 and maybe the GI-11B, both are smaller. This tube is very rae
Brand/ManfacturerNational Union
Same Types
Likely Tyes
Symbol height (mm)17.5
Display0-9
Decimal pointnone
Base0
Starting Voltage (typ)200 V
Maintaining Voltage (typ)0 V
Current per Segment0mA
Reccomend Resistor0