Went to the TRW swapmeet last Saturday, where I traded with Westdave, to get an A107 dekatron. These are in the same glass, with the same structure as the A108 (and A109), but have a different gas mix, different operation parameters, and the glow is barely visible, form the top. Here's a short video:
http://www.dailymotion.com/video/x146fbc_a107-dekatron-selector-demo_tech I rebuilt the selector demo circuit, with 10 LEDs in a circle. One attached to each cathode, to show it in operation, because I had been forewarned that the glow would be almost invisible. This time I left out the shunting resistors across the LEDs. In the A108 circuit I left them in, so that only the cathode that was selected would turn ON. But in reality, the two adjacent cathodes, also conduct some current. In this circuit, that is shown. Also, here I use a neon relax oscillator with a discrete toggle flip-flop, to step the dekatron. The parametric differences here, are: Supply voltage is 510V and anode current of 1.5mA, as opposed to 300V & 0.7mA, for the A108.The commutating step is a 120V, that's biased at 60V, so it steps down to -60V before resting at 60V. <https://lh4.googleusercontent.com/-zTbZe7MAQb0/UidFsJiQtYI/AAAAAAAAMEo/1Lix2qVC_cQ/s1600/A107_2ss.jpg> Enjoy ! -- 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/bd6e1517-d1c9-41f8-acf2-0402aa793ea8%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
