This is a schematic from an article I wrote in 1986.The text is here:-http://www.doc.mmu.ac.uk/STAFF/A.Wiseman/Acorn/BodyBuild/BB_86/BBC40.txt
What kind of frequency and waveform did you use on bit 7. Is there an optimal one?
Many years ago, as an apprentice in the nuclear industry (pre-transistor days) we used to use either 60 or 90volt ( I can't remember which) dry batteries to power the GM tube detectors. It is essential to plot the tube characteristic to find the plateau, as Mike's article shows, so that you get a linear reading. Otherwise you'll be getting bleeps that mean not a lot, especially if your drive voltage is at the upper end or beyond the plateau.
The above link is what I am looking could you explain in terms of that please?
Also could use a 555 in astable mode for my square wave?
Do I need a stable DC voltage output?
Could I use a monostable 555 with a speaker on the output instead of my arduino?
Small signal levels make this design an interesting challenge.
QuoteDo I need a stable DC voltage output?Yes.
zer044,You might check this circuit out. (credit to Tom Napier for the original)It supplies a regulated 200-610V without using a transformer and only draws a few mA.BTW, I wouldn't suggest the SI-3BG tube. It is one of the least sensitive.I have a comparison and sources of GM tubes here.John
part but still leave you with spikes instead of a steady direct current, how does your circuit make your output HV a steady direct current?