Isnt this all so much fun :) we are truly geeks. I would think that if we take a pic using a digital camera with NO OTHER LIGHT of the tube glow we would pull that image into something and get a spectrum from the software ? Not exactly a spectradiometer but this might provide clues to the spectra and gas mix.
Hmmmm..... getters.... Thats a whole different subject.. And how does cold effect them. Yea my 6909's have no getter. None what so ever. Good point on that one. Indeed I will contact that ebay seller. Thanks for the tip :) Ive been playing with the counter more.. I have fixed the issue where I could not trim out the main osc properly. Required a 22pf cap of extra range to trim the aged crystal. I was able to trim it to 100000.050hz. It drifts around .01hz after a 30 min warm up. That seems quite good. My brain is failing me to determine ppm drift for it but its impressive. Good to have it calibrated against a rubidium atomic standard. Thats the actual osc circuit. It then divides it down to 10khz, 1khz,100hz,10hz,1hz. It does this in a analog domain using some kind of harmonic process I dont quite understand. Each 5965 tube somehow divides the input by 10. These produce perfect division with the 1 hz at the end of the chain of 5965's being 1.00000050 This one hz reference is the BIG deal as its the /sec reference that the counter uses count incoming cycles to. IE cycles per sec. BUT a error is creeping in. The counter tubes, the 6909's in question, is missing a few counts. So in the self test mode about 10% of the time it misses 3 counts out of 100,000.. Thats counting to 100,000 in 1 sec mind you and it sometimes misses exactly 3. It misses these exact three, rarely, all the way out to 120khz where then it just falls apart. Im letting it cool off and im going to do a little work on the TXCO ( oven based crystal ) because its case is a little loose. Remember its using 5 dekatrons to count to 100,000 in 1 second and it almost never misses one count. Dekatrons are stunningly reliable counting devices. Below 100khz it seems 100% accurate. I will try using a camera and see if I can catch a spectrum. -- 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/5a70f834-64f7-4c6d-8656-67e5774590f5%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
