Hi all, I recently bought some 6844A tubes of ebay - I fancied making a four tube clock with round top-view tubes. In my head I had assumed that these would be doped with mercury, but they aren't. However, before I found that out I bought four Raytheon JAN 6844A tubes and 2 Burroughs 6844A tubes - I figured if I changed my mind and wanted to make a six tube clock, I might as well have the extra tubes lying around. Another assumption: They would have the same mechanical specs, but they actually look very different - I prefer the look of the Burroughs tubes.
All of them are NOS. So, I tested them and the Raytheon tubes are fine. One had Cathode poisoning (NOS? It was in the original box!). That was easily fixed with some over current and it was fascinating to see that work - this is the first time I have had to do that. The Burroughs tubes are quite a different story. On one of them, half the digits don't light up, but the leads to the digits do! I have posted some pictures below. On the other one, none of the digits light up - only the leads. Well, I'm going to put this down to experience - I am probably not going to build a clock with tubes that aren't doped with mercury - but I would like opinions as to what might be going on with the Burroughs tubes. Note that the behavior is independent of the actual anode current - other than how brightly they glow! This one shows just the lead lighting up: <https://lh3.googleusercontent.com/-z6PoJP4nnLg/WNPjcEjdM3I/AAAAAAAAAgM/ZNebX4kd688dm4tLHQctcx4gKlWhKQ4VQCLcB/s1600/IMG_1285.JPG> This shows the digit 3 and the lead lighting up: <https://lh3.googleusercontent.com/-FqBjwt1dVbQ/WNPjh-0kJoI/AAAAAAAAAgQ/Y3dHcwgftdcZzKl_Hdq-hV6CSKo_Pf9KQCLcB/s1600/IMG_1286.JPG> This shows a lead and a 'not connected' pin lighting up: <https://lh3.googleusercontent.com/-RxhpDHCFwfY/WNPjmNaOt7I/AAAAAAAAAgU/Qpm6i0ZEfQg2-FVLJq-dDXwgij2bSoSOwCLcB/s1600/IMG_1287.JPG> This shows the digit 2 behaving itself! <https://lh3.googleusercontent.com/-WsXz-S9LjuY/WNPjUwcZxiI/AAAAAAAAAgI/IqMWFM_bOCI8zIcgPCgBH98EAZQwRW_0gCLcB/s1600/IMG_1283.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 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/d4b55acf-389d-46cd-9d71-0109ace4e35c%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
