The datashet that John linked to is stuck onto the end of the datasheet for the QT1257, I never found it as a separate datasheet before when looking for it several years ago. I also forgot to say that it seems to me like these tubes were actually named 425 or 425A as the last number varies with the voltage drop, at least it does so on my tubes - so 425A2 is 72V, 425A5 is 75V for the ones I own, but for the 2040's and 1C21's the voltage drop is closer to the 80V stated in the datasheet for the QT1257, and they don't have a sticker or any printed number for the voltage drop. There is one 425A5 at Radiomuseum: http://www.radiomuseum.org/tubes/tube_2040.html which also has 2040 printed on the glass. I guess these tubes were tested at the factory where they were measured and then were either printed or had a sticker with the voltage drop glued to them so they could be used as the correct replacement for the circuit. /Martin
-- 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 neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/cba5178d-0290-4679-b60f-1c663ba66270%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
