Tim, spot on! I finished testing and had a nice pile of mis-behaving tubes that would "snatch" to the other end on the first glimpse of FSD and jump about during ascent and descent. I de-soldered one leg of my reservoir cap so they have a nice 100Hz ripply supply and they all, instantly, work perfectly! The tubes are slightly (only slightly) dimmer and the tops develop a hazy arrow instead of a sharp end to the bar but they slide up and down smoothly and don't seem to mis-behave at all.
I am still, however, convinced that most of mine are some argon-neon mix which is a bit annoying as the few that are true bright orange neon are lovely... Cheers guys, - Alex On Saturday, 5 January 2013 15:15:13 UTC, Tim wrote: > > > > That is very interesting that you are not using a SMPS and still having > the trouble. I have never tried the tubes with a full bridge only a half, > I wonder if the difference between 50Hz and 100Hz makes any difference, I > cant see why it would. > > You say you have a large reservoir cap, effectively giving you smooth DC. > I dont think these tubes like smooth DC hence the SMPS being trouble. Try > removing the cap and see what happens. > > Hope this helps, > > Tim > > > > On Saturday, 5 January 2013 14:30:38 UTC, Alex wrote: >> >> Cheers for the replies guys, I suspect that with a bit of running in most >> of the tubes I have labeled "Slight poisoning" will come right... It is >> strange that your purple topped tubes are distinctly different from white >> topped, maybe I got lucky with my white topped but I defiantly prefer the >> true neon IN-9 glow... >> >> My test rig could not be better for the tubes: >> >> UK Mains -> Isolating TX -> Variac -> Full Bridge -> Large reservoir cap >> -> 25K W/W Pot -> 1K 10W Fixed R -> mA Meter -> Tube. >> >> Defiantly no switching noise! >> >> I will leave a few of the worst offenders on burn in for a half day and >> see if they wake up a bit better.... >> >> - Alex >> >> >> On Saturday, 5 January 2013 11:46:34 UTC, Tim wrote: >>> >>> >>> Hi Alex, >>> >>> First things first, I love IN-9 tubes and am in the process of making an >>> audio spectrum analyser with them. I have both the orange and violet >>> versions. My violet ones having the purple top and do illuminate with a >>> very purple glow :o) These tubes are trouble and very hard to make them >>> consistently illuminate from the bottom as they do not have the extra >>> electrode the IN-13s have. But there is a way! >>> >>> I would be very surprised if your problem is being caused by cathode >>> poisoning, it is more likely to be because of the power supply you are >>> using. These tubes do not like being run off nice clean DC from a SMPS. >>> One must consider that when these tube were first being used (decades >>> before I was alive) SMPS were not used to any extent (if at all?). They >>> were powering the tubes from good old half wave rectified DC. I personally >>> power the tubes from a mains isolation transformer (I think it came out of >>> a bathroom shaver socket) and a single 1N4007 rectifier diode. I don't >>> think I have ever had one misbehave being powered in this way. Give it a >>> go and see if this solves your problems. >>> >>> Don't forget that the IN-9 are very power hungry compared with that of >>> the IN-13. >>> >>> Hope this helps, >>> >>> Tim >>> >> -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msg/neonixie-l/-/lk7feEQN5CkJ. For more options, visit https://groups.google.com/groups/opt_out.
