I wasn't home at the time, and all I had were three 10k trimpots :) Why is that bad? I would leave it that way, if that's ok.
On Mar 16, 8:27 pm, Adam Jacobs <[email protected]> wrote: > Why are you sharing 1 anode resistor across two tubes? :) Is board space > at that much of a premium? > > On 3/16/2012 12:18 PM, Imbanon wrote: > > > > > > > > > First of all, thank you all for your support. Feels great to have some > > people with knowledge behind my back. > > So many replies since I had time to check the group last time that I > > don't know where to start :) > > > I do not have a schematic for my design, as it is my own design that I > > pretty much pull out of my head as I go. That often shown like a bad > > idea, making me to change a lot of things afterwards. Just like today, > > I had to rewire the whole 'spider web'. And that was the second time I > > had to do it! > > And I have to clear out that I have a common anode resistor for 2 > > tubes, making a total of 3 anode resistors for all 6 tubes. That means > > that the current has to be double (resistance cut by half). I hope > > that it now explains the rounded 8mA (7.74 to be more precise) on the > > anode resistor. It cuts to two nixies, giving appox 3.87mA peak > > current to each tube. So then 3.87*sqrt(0.267)=2mA RMS > > Anyhow, I do believe that I have to use the RMS values when working > > with multiplexed designs, rather than average. Just like someone > > already explained why, because of the power dissipation. I really hope > > it is that way :) > > > Well that's all for now. I hope that my setup with anode resistors is > > finally done. If not - I still have another week to use all the fancy > > expensive oscilloscopes! So if anyone doesn't agree with this, please > > say the word :) > > > Cheers > > > On Mar 16, 9:13 am, Dekatron42<[email protected]> wrote: > >> Many manufacturers write that you will have to contact them for the > >> special curves you need when you are going to multiplex their Nixies > >> since they do not usually print that information in the databooks. > > >> These sheets show you that the Nixie will have an increased turn-on > >> voltage corresponding to the increased current when run in switched > >> mode. This is the same as when a neon voltage stabilizer tube is used, > >> the voltage increases somewhat when the current increases, you can > >> check the OB2 voltage regulator tube for instance. > > >> The curves for most Nixies when used in multiplexed mode are not > >> linear so if you can't find those curves you'll have to make the > >> measurements yourself and take into account the spread between > >> different Nixies to draw the curve. Some of these special curves have > >> a voltage span of approximately 10-30V for a certain current through > >> the Nixie, so there is an upper and a lower limit for the turn-on > >> voltage corresponding to the current used. > > >> This book:http://www.oldtimeradio.de/BU7908.php"Electronica 171 - > >> Elektronische Anzeigebauelemente" by Winfired M�ller contains a few of > >> these curves for the ZM-series of Nixies. > > >> /Martin > > >> On 16 mar, 00:55, Cobra007<[email protected]> wrote: > > >>> Yes, I think I mentioned "slightly" increase rather than a mayor > >>> increase. > >>> I have measure this on another nixie tube and came to the following > >>> voltages: > >>> 0.5mA : 120V > >>> 1.0mA : 125V > >>> 1.5mA: 130V > >>> 2.0mA: 133V > >>> 3.0mA: 140V > >>> 4.5mA: 150V > >>> His tube current will increase from 2mA to about 7.5mA, so according > >>> to the above measurements, the increase in tube voltage will be > >>> playing a role. > >>> Michel > >>> On Mar 16, 10:06 am, Charles MacDonald<[email protected]> wrote: > >>>> On 12-03-15 05:46 AM, Cobra007 wrote: > >>>>> So it looks like your resistor is correct. The only thing is that the > >>>>> voltage across the tube will slightly increase due to the higher > >>>>> current, so it's not 100% correct but pretty much. > >>>> Since we are talking a Neon device, the voltage across the tube will try > >>>> to stay the same, with the current adjusting if needed. That is why > >>>> Neon bulbs were used as Voltage reference devices in days of Old. > >>>> -- > >>>> Charles MacDonald Stittsville Ontario > >>>> [email protected] Just Beyond the > >>>> Fringehttp://users.trytel.com/~cmacd/tubes.html > >>>> No Microsoft Products were used in sending this e-mail. -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. 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.
