I will draw up a schematic of what I have in the panel now. I think it'll probably be similar to what the otis docs show: resistor connected in series with the tube, trigger and cathode tied together, and connections for B+ and 'B.O.' (B.O. being the reference line for B+, which also happens to NOT be at the same potential as ground, due to the AC supply tied to it). There seems to be a cap, probably in parallel with something, but I'll take a look.
On Wednesday, October 22, 2014 4:51:21 PM UTC-5, Dekatron42 wrote: > > I think that the best thing you can do is to ask the company who replaced > it if they can help you with any schematics, otherwise you will have to > draw one yourself from what you have left of the elevator panel and we can > take it from there, then you will know what voltages you need and you can > do some experiments more easily. > > /Martin > > On Tuesday, 21 October 2014 21:00:47 UTC+2, Joe Zatarski wrote: >> >> I guess now what I would like to know are some example circuits for power >> supplies maybe? I guess I need 135VDC, and it needs to be isolated from the >> mains because it'll also have 150VAC on it relative to earth ground. >> Easiest to do is get a transformer (if I can find the right voltage output) >> but how about regulation? Is a properly sized zener diode good enough? >> >> On Monday, October 20, 2014 10:41:47 AM UTC-5, Joe Zatarski wrote: >>> >>> So I found an elevator control panel in the garbage. They were replacing >>> a broken one in the dorm next to mine. It appears to have 425A5 'touch >>> tube' trigger tubes instead of mechanical switches. I saw an old thread >>> here about them which had a bit of info. I think you need to connect a >>> 150vac supply between ground and the cathode, then 135vdc across the anode >>> and cathode to use them as a touch button. There needs to be some >>> resistance in series with the tube of course, and the 135vdc needs to be >>> isolated from the ac. Also, I think the trigger input needs to be tied to >>> the cathode somehow. >>> >>> I still have all the wiring in the panel as it was when I found it. >>> There are 12 floors and a basement, so I'm thinking the buttons can >>> represent the hour of a clock as well as an am/pm light. Furthermore, for >>> setting the time, the tubes can still be used as buttons to type in the >>> time. >>> >>> I'd appreciate if I can get some tips on driving circuitry and supplies >>> since these are cold cathode neon tubes, something I have never dealt with >>> before. >>> >>> -- 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/7ab268e7-dd97-4fc3-b96f-8a72f5466838%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
