Speaking from considerable experience; you must drive the older date code IN-18 tubes at beyond 5ma cathode current to limit the effects of cathode poisoning. The 1980-1983 production tubes are a particularly nasty batch, tending to form oxides on active cathodes in spite of the excessive current.
The 1989-1991 production IN-18's are the best, and typically will operate problem-free at <4ma. I had thrown away hundreds of older date coded IN-18 tubes because of recurring oxide poisoning or frit seal leaks. I'll wager that Dieter also has a growing bin, laden with stinkers ;) Regards, Jeff On Monday, July 2, 2012 2:43:43 AM UTC-7, marcin wrote: > > So, where is the catch in this: http://www.ebay.com/itm/310407744076Looks > fishy. Of course I have no affiliation with this seller nor I ever > bought anything from them. -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To view this discussion on the web, visit https://groups.google.com/d/msg/neonixie-l/-/6X_YjeKaLIoJ. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
