Yes, I've seen it on quite a lot of these. I bought some lots of these perhaps 15-20 years ago and when I complained to the different sellers on eBay they said that they had stated that they were factory rejects due to the filaments being to far from the segments and also not equally spaced to cover each others fields linearly - I could never get that confirmed from anyone and I got a refund and got to keep them - I've been waiting for someone to come up with the true reason for this banding for all of these years, and also for someone to publish a design on how to drive them properly!
I have seen some that doesn't seem to have this banding but those photos are from to far so I couldn't really see if there is some banding in those displays. I was experimenting with higher lower voltages/currents and also tried to "refurbish" them as you can do with the VFD-displays for Hewlett Packard instruments that use them by over-driving the filaments so they start to glow slightly orange but that didn't help either - I've successfully refurbished HP-displays that way so I know that way of refurbishing works. I tried to have a good look to see if there was anything askew with either the filament threads or the grid thinking that it could be a manufacturing problem with either that results in this effect but the rounded edges didn't let me have a good look of the insides so I couldn't really confirm anything. So now I keep my fingers crossed that someone will chime in here and explain it all! /Martin On Sunday, 23 November 2025 at 12:33:01 UTC+1 Richard Scales wrote: > I have just started testing this display and I am using an A/C supply for > the filament and 24V for the grid and segments. > > I am seeing some interesting artefacts on the active segments and am > wondering if anyone else from the group has seen similar? > > I have tried different power supplies for the grid and segments, both hard > wired and HV5812 driven segments and with/without series resistors on the > grid and segments. > > Has anyone seen anything similar? > > - Richard > > [image: ILC1VFD.jpg] > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion, visit https://groups.google.com/d/msgid/neonixie-l/c4f92d4a-aeca-408f-907d-dd6a03f4842an%40googlegroups.com.
