On Jan 2, 9:56 am, Nick <[email protected]> wrote: > Given that most of us had a bit of time off, what new toys have you > been building/acquired?
Well, funny you should mention that... After 18 months or so pretty exclusively researching and playing with dekatrons, I've come back to clocks and nixies a bit over the last few weeks... I bought a Bulbdial kit from Evil Mad Science a year ago, and finally got round to assembling it. More details here (http:// evilmadscience.com/tinykitlist/156) for the curious. It's (cough) LEDs rather than tubes, but a neat concept and well designed, though the hour hand could be implemented somewhat better IMHO. And, I've returned to a large multiplexed nixie design that's been gathering dust in what my wife laughingly refers to as my 'toy cupboard' for a couple of years. Dusted down the prototype jig, added another board, remembered how the firmware worked and it's humming along very nicely indeed now! Needs some more development, but the basic concept is working sweetly - a few more months and there should be something interesting to share :) Getting back into that design reminded me of the value of a couple of things associated with this group. First, there's the wealth of experience locked up in our message archives over on the Yahoo site. In the new design, I hit a problem with variability in the intensity of decimal point indicators depending on whether or not the tube also has a digit illuminated. Ten minutes rooting round the message archive confirms the suspicion that it's a current sharing effect and provided several suggestions for fixes, including a very neat trick from Peter Hand which not only mitigated the problem significantly, but also saved me a resistor on what will be a cramped board layout. Secondly, the HV PSU modules developed by various group members make developing new nixie designs so much easier. I've rolled my own PSUs for several clocks in the past where they had unusual requirements, but for general use it's difficult to beat something the size of a postage stamp which does exactly what you want and takes no cycles from the MCU to manage. Plus all the sensitive layout stuff is already done and contained within the module, so you can just pipe the HV directly into a nasty hacked up veroboard prototype without having to worry. My total favourite at the moment is John Taylor's 1363/1364 design which is a real triumph of the circuit designers' art. So, happy New Year to all and thanks for all the good things from previous years! Cheers, Jon. -- 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.
