-mm special tube manufactured by Htiachi

The H1544 is a special character nixie tube. I found out that this logo on the tube is an old hitachi logo, so this tube was manufactured by Hitachi. It can display roman numbers from one to three, a minus sign and a special symbol. If you power the minus sing and the special symbol at the same time the letter E is displayed. There is a smiliar tube, the H1501, which lacks the roman three symbol.
Brand / Manfacturer Htiachi
Same Types
Likely Tyes
Symbol height in mm -
Characters / Symbols special
Decimal point none
Base / Socket 0
Starting Voltage (typ) 150 V
Maintaining Voltage (typ) 0 V
Current per Segment 0mA
Reccomend Resistor Tested with 150V and 18kOhm