A 5 Volts power supply is a big limitation regarding to a current source compliance. I'd do the following:
1 - Decouple the outputs of the filters from the rectifiers, so as to have an output voltage referenced to 0 and up to 5 volt. The rectifiers act as peak detectors and your signal moves from 0 to 5V before clipping. 2 - Build a current mirror sink to ground, knowing beforehand that close tracking of discrete devices is an utopia, per output tube (I support the IN-13 advice). 3 - Inject the minimum bias current and sum up with a variable current to swing the total needed by the tube. This, done with simple resistors to +5V and the output to unity gain buffers (LM324 will work fine). I'd try to make a schematic when I get time, but the circuits are very simple. Gastón On Monday, October 7, 2019 at 7:09:38 AM UTC-3, Mateusz Dziuba wrote: > > Hi again! > > > After abandoning the project for a long time I came back to my IN-9 tubes. > I replaced the PSU (NE555 based -> MC34063A based), replaced transistors > for MJE340 (which will be used in final design) and did a bit of burning of > each lamp separately. Finally I get to the top of the tubes (well 9,5 mm). > It seems lamps required to be burned with higher current which my previous > PSU, current mirror and potentiometer arrangement was not able to provide. > I am blaming poorly designed PSU. > I would like to thank all of You for your time and advices. > > Now I am facing another problem. > > I built set of band-pass filters using LM324 with single supply 0-5VDC. As > the 2.5VDC is feed to non-inverting input of op-amps, and audio signal is > feed on inverting input, the value is oscillating around 2.5V (middle of > nixie). I was planning to use microcontroller and map the output voltage to > 0-5V by software and then feed on MJE340. in the end I decided to not use > microcontroller, and now I am stuck at point "How to get a 0-max swing of > the bar on the nixie?" > >> -- 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 on the web, visit https://groups.google.com/d/msgid/neonixie-l/4aff2f97-4c49-447e-af60-f5772bd56f53%40googlegroups.com.
