Re: [neonixie-l] VFD filament drive

2021-09-01 Thread 'John Rehwinkel' via neonixie-l
> I wonder why there should be no air gap? Air gaps lower the inductance, but stabilize it and store energy in the gap. Working forward from this, you generally find flyback type circuits use gapped cores, and others generally instead opt for best coupling and highest inductance. - John --

Re: [neonixie-l] Newbie would like to introduce himself

2021-09-01 Thread Bill Notfaded
Wow Rich I have some panaplex and devices with them but the model you mention is rarer it seems. I wonder if they were used in some arcade games as I found a picture here: https://www.andysarcade.net/store2/images/source/comp/disp05.JPG You can see the common for digits on the right and one

Re: [neonixie-l] VFD filament drive

2021-09-01 Thread David Pye
For mine I used one of those cheap eBay buck converters. 5v in, 1.x v out (adjustable). 8 iv11 tubes, running for a few years without a blip. If you needed AC, you could always just use an H bridge and a microcontroller pin to flip it at a suitable frequency with a smoothing cap. I found I

Re: [neonixie-l] VFD filament drive

2021-09-01 Thread Dekatron42
You can use airgaps in transformers in some cases but this design should be without one according to Ed. I am using ferrite pot cores in some other designs where they are wound as a transformer but where the Q-value is of importance and there I use an airgap and also a trimmer through the

Re: [neonixie-l] VFD filament drive

2021-09-01 Thread Paul Andrews
Martin, I wonder why there should be no air gap? - Paul On Wednesday, September 1, 2021 at 1:55:30 AM UTC-4 Dekatron42 wrote: > Paul, > > I'll ask him, but a quick search at Digikey showed both some RM10 and > ETD29 cores, but only a few. Finding Ferrite cores today is not easy, I > have