Still a bit of juice left! Sent from my iPhone
> On Nov 26, 2020, at 07:25, Paul Andrews <[email protected]> wrote: > > Finally got an alpha detector for my GK-Mini geiger counter. First picture > is a regular nixie tube. Second is one doped with Kr85 > <IMG_5681.JPG> > > <IMG_5683.JPG> > > >> On Friday, November 6, 2020 at 9:20:54 AM UTC-5 SWISSNIXIE - Jonathan F. >> wrote: >> Could also be Ra-226 on the 6140 >> >> gregebert schrieb am Mittwoch, 4. November 2020 um 16:32:02 UTC+1: >>> Maybe it's Thorium, used in the filaments. >>> >>>> On Wednesday, November 4, 2020 at 4:13:16 AM UTC-8 Paolo Cravero wrote: >>>> Hi. >>>> Let me add two pictures and a story. >>>> >>>> Lately I picked up locally a bunch of small CRTs (2BP1, that also fit in >>>> the vintage tuner currently on eBay, plus a Marantz) and the guy had a few >>>> NIB tubes too. I was looking for gas-filled ones and that resulted in a >>>> W.E. 6167 dekatron, some 0B2WA and some W.E. 6140/423A. Of particular >>>> interest was the 6140 shown in the picture whose box mentions Kr85, but no >>>> symbol on the glass. >>>> When I came home I checked with a Geiger counter and SBM-20 probe (hard >>>> beta and gamma particles) these tubes and the 6140 from 11/61 shows no >>>> action. Same goes for other 6140 except for one, much older from 12/52 >>>> marked 423A. Neither the box nor the glass carry any warning sign, but >>>> this tube hits >600 CPM vs 40 CPM background when put close to the SBM-20 >>>> probe (it's not the right way to measure radiation, but it's cool :) ). >>>> There is definitely something else than Kr-85 in there! I have blurred >>>> pics of it and it has been stored away from home. >>>> >>>> As already mentioned, Nixies did contain Kr-85 and I knew I had one >>>> clearly marked. It's a Burroughs Self-Scan display that probably needed >>>> some "doping" to handle the almost 1 MHz scan rate. BTW, it contains gas >>>> and I might never use it, so if someone wants to experiment with self-scan >>>> contact me off the list. >>>> >>>> One question for the knowledgeable people in here. I have some Mullard >>>> Nixies marked "Kr-0A": has it got something to do with Kr-85? I can't >>>> check with the Geiger since my probe does not detect Kr-85 leftovers. >>>> >>>> So, if you are on the hunt for active tubes, better look for unmarked >>>> pre-1960 editions and carry a Geiger counter with you ;) >>>> >>>> Paolo > > -- > 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/3f26a1e5-5836-4ff5-b1ea-f95fab53151cn%40googlegroups.com. > <IMG_5683.JPG> > <IMG_5681.JPG> -- 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/09D0025B-B060-43F7-8277-B253283111CA%40gmail.com.
