Most likely, the error is in the text description in the instruction manual. From the datasheet, pin 9 is the multi-anode connection, and pin 5 is the single anode. I am more likely to follow the connections to specific pin numbers in the instructions, rather than the text-description. Pin 9 is the higher-voltage (1500V) anode, and it should not be difficult to verify that in the schematic.
As far as the power is concerned, I cant figure out where 7-10 watts is going. The filament is 6.3V / 150mA so that's less than 1 watt. The electron-beam current is probably less than 100uA, so that is also less than 1 watt. For comparison, a NIMO tube uses 30uA. Even if the anode current was a whopping 1mA, that would still be only 1.5 watts. So that leaves the grid and focus anode as the only other source of power dissipation; maybe some clues will be in the schematic. My kit arrived in the US earlier this week, so I hope it will get delivered to me next week. I will be placing a 250mA fuse in series with the filament for added protection. I'll post an update after I've either finished it, or ran into a problem. On Friday, May 14, 2021 at 5:15:45 PM UTC-7 John Snow wrote: > Found a conflict between the documentation (both before and after google > auto-translation). The conflict is between Anodes A1,A2,A3 in the sellers > documentation. > > The seller's documentation lists: > > A2 (Focusing Anode) - pin 5 > A1,A3 (first and third anodes) - pin 9 > > I've found a separate pinout for the 8SJ31J tube that lists: > > Focusing Anode,A2 - pin 9 > A1 - pin 5 > > The second pinout is from > http://www.spectrum-scientifics.com/v/vspfiles/pdf/Properties_of_Electrons_Apparatus.pdf > > > It looks like the tube in the spectrum-scientifics is the thin-pin version > of the 8SJ31J, and the kit uses the thick-pin version of the 8SJ31J, but > I'd like a second opinion. > > I know they have different power requirements - the thick-pin (old) is > around 10W, and the thin-pin (new) is around 7W (I'm assuming which are old > and new based on the design of the base socket). The rest of the pinout > agrees, is this another difference between the old and new designs of > tubes? > > Tl;DR I'm not clear on the anodes of the 8SJ31J, which pin is the focusing > anode, and why the other two of the three anodes are joined together. > On Saturday, 15 May 2021 at 00:06:33 UTC+1 John Snow wrote: > >> I'm trying to figure out how it's put together before I start soldering. >> >> As Paolo mentioned the only mystery part is the transformer T-SC-1 on the >> parts list - it looks like a custom order. I don't know how to characterise >> it without destructively pulling it apart, and unfortunately they don't >> sell them separately. >> >> There's another four without the tube now listed: >> https://www.ebay.co.uk/itm/265151344483 >> >> The kit is listed as configured for 8SJ31J by default, and the >> documentation linked further up lists the wiring for 3SJ1J/5SJ38J/7SJ32J. >> No idea if the power requirements differ and requires resistors changing on >> the circuitboard(s), or if they are plug-and-pray drop-in replacements once >> you've changed the pinout. >> >> The auction page says it can be used with >> 3LO1I/7SJ33J/8SJ31D/8SJ40/8SJ42J/8SJ40D/9SJ105Y14/12SJ102J/13SJ38J/13SJ38D. >> Unfortunately without knowing the transformer operating characteristics >> I'd be hesitant to plug in anything else. >> >> I'll probably try to replace the fuses with polyfuses in the future, >> socketing them for now, and taking measurements while unpopulated for >> easier case design later. >> >> >> On Wednesday, 28 April 2021 at 20:25:12 UTC+1 John Snow wrote: >> >>> Huh, ebay auction says 12V 5A, a previous aliexpress page gives much >>> lower values for amperage: >>> >>> https://www.aliexpress.com/item/4001142939399.html >>> >>> I'm assuming it's the same design from the pictures >>> >>> On Wednesday, 28 April 2021 at 20:18:53 UTC+1 John Snow wrote: >>> >>>> The kit was previously 'avalible' from aliexpress for £56.44, but it >>>> was from a seller that held no stock - got refunded as unable to ship. >>>> >>>> That was minus the tube though, the current ebay link includes the >>>> 8SJ31J but lacks a power supply (12V 5A centre+) >>>> >>>> Unsure on lifespan of tube. >>>> >>>> On Wednesday, 28 April 2021 at 19:46:03 UTC+1 Paul Andrews wrote: >>>> >>>>> They actually seem very cheap to me... >>>>> >>>>> On Wednesday, April 28, 2021 at 12:56:00 PM UTC-4 John Snow wrote: >>>>> >>>>>> There's another 4 of the 8SJ31J kits listed at >>>>>> https://www.ebay.co.uk/itm/265139148431 , I've ordered one on the >>>>>> offchance they have them in stock, also the seller has feedback for >>>>>> selling >>>>>> them previously. >>>>>> >>>>>> Bit of a premium tho, and only avalible with tube. >>>>>> On Wednesday, 16 December 2020 at 11:40:02 UTC Collin Smith wrote: >>>>>> >>>>>>> Have you looked at these kits? >>>>>>> >>>>>>> https://oscilloscopeclocknixiecrt.com/Kit.htm >>>>>>> >>>>>>> >>>>>>> Sent from my iPhone >>>>>>> >>>>>>> On Dec 16, 2020, at 00:17, John Snow <[email protected]> wrote: >>>>>>> >>>>>>> I've tried to get that one from Aliexpress previously, but they >>>>>>> later refunded me saying they weren't getting any more stock. >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Friday, 11 December 2020 at 21:42:35 UTC Pramanicin wrote: >>>>>>> >>>>>>>> Did anyone else on the list buy one of those recent CRT clock kits >>>>>>>> that was listed on eBay? >>>>>>>> >>>>>>>> like this one... >>>>>>>> >>>>>>>> >>>>>>>> https://www.aliexpress.com/item/4001330655526.html?spm=a2g0s.9042311.0.0.1a084c4d8VxYDr >>>>>>>> >>>>>>>> I have a kit, but they never shipped the instructions, so if anyone >>>>>>>> has some that would be great. >>>>>>>> >>>>>>>> Thx, >>>>>>>> >>>>>>>> Nick >>>>>>>> >>>>>>> -- >>>>>>> >>>>>>> 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/3aacb083-5cbf-4b96-96ee-6e8e13744159n%40googlegroups.com >>>>>>> >>>>>>> <https://groups.google.com/d/msgid/neonixie-l/3aacb083-5cbf-4b96-96ee-6e8e13744159n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>>> . >>>>>>> >>>>>>> -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. 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