I have three mod six's. While it's not a huge sample size, that's still 18 previously-used B-7971's. And I don't event know how many hours they had on them originally (although none are blackened and none have cathode poisoning, so hours can't be too high). But certainly, all 18 tubes are used. And despite that, I haven't had a single tube failure over the past three years. That's pretty darn good. In comparison, a number of the IN-18 based clocks that I have assembled have had their tubes fail very quickly, mostly due to degassing (I presume from slight later forces on the pins causing the hermetic seal to fail).
By comparison, I would offer that the B-7971 is a remarkably durable tube, if driven properly with anti-poisoning patterns. -ub On Tue, Jun 13, 2017 at 5:22 PM, Nicholas Stock <[email protected]> wrote: > Has anyone experienced a B7971 failure 'in service'? My MOD_6 looks as > good now as it did when I first turned it on....I wonder what the true life > expectancy of these tubes is.... > > On Tue, Jun 13, 2017 at 1:53 PM, Ulysses Balis <[email protected]> wrote: > >> The mod-six is a solid performer. I have three units. All are still >> well, after 1000's of hours of run-time. >> >> The original kits were about $550 and the B-7971 tubes, when you can find >> them, go for $80 and up. So $1200 is fair, albeit a bit high, for a clock >> with substantial hours. A photo of my office clock is attached below.... >> I love this clock. >> >> >> >> On Tue, Jun 13, 2017 at 11:15 AM, gregebert <[email protected]> >> wrote: >> >>> For those who cringe at the 1200 USD price, rest assured it's a fair >>> price >>> >>> I'm in the midst of writing the software for my 8-tube b7971 clock, and >>> the scarce supply of the tubes plus the time it takes to design, build, and >>> debug makes it a costly project to do it on your own. I never thought I >>> would want one until I literally got to hold one of those 70+ mm-tall >>> beasts in my hand. Those tubs are really big. >>> >>> -- >>> 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 email to [email protected]. >>> To view this discussion on the web, visit https://groups.google.com/d/ms >>> gid/neonixie-l/6de6235f-aad3-4c51-80a7-ac11191ebe7d%40googlegroups.com >>> <https://groups.google.com/d/msgid/neonixie-l/6de6235f-aad3-4c51-80a7-ac11191ebe7d%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- >> 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 email to [email protected]. >> To view this discussion on the web, visit https://groups.google.com/d/ms >> gid/neonixie-l/CANX%2BaJhu2_uS6OYDpHSbo3d5ijz%3Diz6bEH4L2cOW >> BeGyZ6cs1g%40mail.gmail.com >> <https://groups.google.com/d/msgid/neonixie-l/CANX%2BaJhu2_uS6OYDpHSbo3d5ijz%3Diz6bEH4L2cOWBeGyZ6cs1g%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> >> For more options, visit https://groups.google.com/d/optout. >> > > -- > 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 email to [email protected]. > To view this discussion on the web, visit https://groups.google.com/d/ > msgid/neonixie-l/CAOX%2BRHLot33WxupP%2B9bQffzvJpizNLjxz0x%2BgB%3DK_ > WK1owAndA%40mail.gmail.com > <https://groups.google.com/d/msgid/neonixie-l/CAOX%2BRHLot33WxupP%2B9bQffzvJpizNLjxz0x%2BgB%3DK_WK1owAndA%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > For more options, visit https://groups.google.com/d/optout. > -- 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/CANX%2BaJgVE6h6j63XuV8f%3DqTdDHBcShxLygw-1TskTqA_w9u_EQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
