On Mar 9, 8:46 am, "JohnK" <yend...@internode.on.net> wrote: > How about you check the tolerance % of the resistors. Did you use 10%, 5% > etc ? > And, how about you measure the voltage drop across each of the anode > resistors in turn.... and with different digits ON. > > BTWQ, that current increase is not large.... BUT, it may not be spread > evenly across the tubes; what if it is one tube drawing all the extra?
Further to that - accurately measure each anode resistor, then measure the voltage drop across them, then for each work out the current - you should probably use a BIG digit, such as "8" to do this. Generally, the life of a nixie exponentially decreases with increased anode current. I would probably aim for an average of 2mA per digit, and 1.5 may be enough, i.e. always err on the low side. Bear in mind that this is NOT precision science. 10% or worse resistors were commonly used, and the characteristics quoted for tubes are really an idealised average over a sample. Note that the current requirement for a given level of illumination is related to the surface area of the digit. Some tubes are cute about this and make the "1" fatter and the "8" skinnier etc. to compensate, but this is not always the case. So, relax a bit, aim for about 2mA or a bit less, and stick with that. Note the decimal point is max rated at 0.3mA Nick -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.