http://i.imgur.com/CFTb8gI.png
is this what you mean? Eagle was being weird today so I had to draw it in lochmaster Why is that better than the original two ideas? I would like to understand everything :) Op dinsdag 19 november 2013 21:48:18 UTC+1 schreef nixiebunny: > > On 11/19/2013 1:36 PM, John Rehwinkel wrote: > >> I want to build a four digit VFD clock (three of them actually) without > using drivers like the max6921. I have two possibilities at this moment, > one is this http://i.imgur.com/D4FGaV1.jpg > >> and the other being this one http://i.imgur.com/5fMc7ty.png . > >> Which would be best? > > > > I'd use the more traditional design with a resistor in series with the > base of > the NPN transistor driven by the CPU, rather than the emitter resistor as > you > showed. > > More or less like this: > http://www.dos4ever.com/nixie1/multiplexing.gif > > That resistor R5 from base to emitter of the PNP transistor can be a lot > lower > value, as low as R6/Vanode. It will make the anode turn off faster, the > lower > resistance it is. > > The transistors can be any type rated for more than the VFD anode supply. > > Also, if your VFD is too bright, you can reduce the brightness by reducing > the > duty cycle, which is done by turning off the anodes on for some time in > each cycle. > > -- > David Forbes, Tucson, AZ > -- 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 post to this group, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/605f3a58-2171-4e25-8437-89bde256c741%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
