Salvaged this old POS display with a dim vacuum fluorescent display in it. This is USB 5V version, fully DC.
Been reading about these VFD rejuvenations possibilities.
I tried supplying around 11,5v DC from some old computer PSU do the outermost pins some seconds a few times.
Only a couple of the segment display areas from top left lit up, no general improvement in brightness.
I was under impression those filament lines/grids should start glowing instead.
Should I try more voltage to those same pins? I have no clue really.
This USB version is really easy to program with python.
I was thinking some chatgpt api app for fun, or maybe a guitar tuner or smth.
![Cheesy :D](https://www.eevblog.com/forum/Smileys/default/xcheesy.gif.pagespeed.ic.KPzuH4J-TG.png)
![VFD rejuvenation USB 5V CD7220 1919529-0](https://www.eevblog.com/forum/index.php?action=dlattach;topic=399708.0;attach=1919532;image)
![VFD rejuvenation USB 5V CD7220 1919523-1](https://www.eevblog.com/forum/index.php?action=dlattach;topic=399708.0;attach=1919526;image)