Re: [neonixie-l] Introduction & Telefunken Varisymbol alphanumeric advertisement sign ZM1350 ZM1360 & ZM1370

[Paul Andrews]

Regarding ZM1370 - I literally posted a link to my photos of one earlier in a reply to your initial post. On Nov 24, 2023, at 6:59 PM, Magnedyne <miro.sigm...@airgrips.de> wrote: Alright I’ve done some more research and it appears that this sign might even more special than I previously thought. Some have claimed that Telefunken never sold the ZM1360 and ZM1370 due to them turning out not economically viable. The datasheet for the Varisymbol mentioned datasheets for the ZM1360 and 70 being worked on. I have furthermore found no documentation regarding the ZM1360 and ZM1370 ever being commercially sold. Now of course a lack of documentation is in no way proof but I’ve also not been able to find anyone, or even pictures for that manner, of these two tube types.  If this were to be true I’d have pre production, or rather sample tubes as production never happened. I’m very glad that none of these seemingly nonexistent tubes are „defective“/have a coating. Terry S schrieb am Donnerstag, 16. November 2023 um 01:10:31 UTC+1: I agree, don't change a wire! It's a piece of history as-is. Fix any defects and let it live as a tribute to the original designer. Who are you (or any of us) to second guess the designer? Could you update it with an Arduino and make it do back flips?  Yes of course But should you? No. On Wednesday, November 15, 2023 at 6:36:09 AM UTC-6 Magnedyne wrote: I'll probably leave it as is. I find the curiosity/historical aspect to be more interesting and important than having something which has a use. It's just like the homemade computerkits I collect, each tells their own little story. Some are unfinished, who knows for what reason maybe something got in the way, somebody lost motivation or something else entirely. I wouldn't even think about finishing these kits just to have a functional computer, it's more interesting this way. Yes I'm certain the tubes are not socketed. The baseplate has holes drilled in it which the leads poke through. The unused leads have been bent to the side so that the tube stays in place. I'm uncertain if glue has been used. The wires are soldered to the pins directly. For now I'll keep it running for some time, like Terry suggested, maybe the tubes will come back on their own but I certainly doubt it. Alex schrieb am Mittwoch, 15. November 2023 um 09:48:07 UTC+1: Nice Find. Looking at those pics it seems clear to my eye that this has cathode resistors rather than anode, one for each used cathode. These will then likely be in three groups, Telefunken only, Varisign only and common to both. This then yields one anode wire to all (red wire?)  And three cathode wires (three blacks). It does look like they have only put tails on used cathodes. Circuit is likely a simple astable / flip flop with a pair of big transistors for switching the cathodes, maybe with a variable amount of capacitance on its base for the fade effect? I would suggest an apprentice build back then, maybe the mechanics are nice but I would say the electronics are fairly hum-drum. My approach with this would be to remove the resistor strips, add missing cathode wires, make up some ruler like PCBs with serial HV latches on and replace the main veroboard with a PCB with your favourite micro / embedded solution. This can take in / use the original switches and transformer so with the back on it would look the same. You can then keep the bits removed for archive or if there is enough space, mount new bits on top as a mezzanine. Depends on your goals really, but as is it's more of a curio / collector asset only really... It would blow their minds back then to have scrolling dynamically updated text, and would make use of all the segments (assuming those have not been poisoned to oblivion with deposits). For your current segment poisoning, you could parallel another fairly high R resistor across the existing ones for that tube to up the drive. Certainly no multiplexing going on here! Are you certain they are not socketed? Looks odd with the wires disappearing into the material like that. Best of luck! - Alex On Wednesday, 15 November 2023 at 07:34:47 UTC Magnedyne wrote: -- You received this message because you are subscribed to a topic in the Google Groups "neonixie-l" group. To unsubscribe from this topic, visit https://groups.google.com/d/topic/neonixie-l/8YTUwZ7OvAM/unsubscribe. To unsubscribe from this group and all its topics, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/51f5301e-4a18-462c-9708-46475964f58dn%40googlegroups.com. -- 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 view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/D45EC133-9E44-477D-9753-E5EF430C0A05%40gmail.com.