Hi Jon, Patent CA575269 mentions the G10/241E and also some on the "screen" electrode and its workings. i have not dug deeper into the inner workings, just accepted that the "screen" electrode helps in forming the electron path and enhances the process of stepping the tube. /Martin On Saturday, February 16, 2013 11:59:05 PM UTC+1, Jon wrote:
> > The most curious thing about the A201 is pin 9, whose function translates > as 'screen' or 'shield'. It's not shown in use on any circuit diagram I've > seen for this tube. > > The only other counting tube I'm aware of with such a structure is the > G10/241E Nomotron (and of course the 11TU7 lookalike). The datasheet for > that also does not discuss the function, but specifies that it be set at a > +90V bias. J B Dance (Electronic Counting Circuits) suggests that the > purpose of the shield is to confine the glow to the required part of the > tube. It could well be a similar function for the A201. In the polyatron > configuration, unlike the dekatron, the discharge glow is associated with > the common electrode rather than the electrode which is spatially specific > for each counting position. This may mean that additional measures like the > shield are required to stop the glow spreading across the common cathode > and degrading the counting performance. > > It's interesting that Marcin's datasheet says that the glow is purple, > whereas every A201 I've ever seen is neon-orange... > > Jon. > >> > > -- 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/msg/neonixie-l/-/MYDvdaDejs4J. For more options, visit https://groups.google.com/groups/opt_out.
