Hi Ron, You could try two resistors of 47K in series, between HV and GND. Connect a diode 1N4148 or something, cathode to this voltage divider. Connect the anode to the collector of Q9.
Your nixies are fine, because the 74141 has internal clamping zener diodes. Frank From: Ron Schuster Sent: Friday, September 07, 2012 4:39 PM To: neonixie-l@googlegroups.com Subject: [neonixie-l] NE-2 lamps not fully blanking I've built a 4-digit IN-17 nixie clock based on a 1x4 mux design. It uses 4 neon lamps, 2 for the colon, 1 for the PM indicator and 1 for the Alarm On indicator. I have a small problem where I see a dim flicker in the lamps that are supposed to be off. They are driven as part of the nixie multiplexing circuit. One side of each lamp is tied to one of the digit anode drivers. The other sides are tied together and pulled to ground through one common MPSA42 "cathode" driver. I think I have sufficient blanking time between the digits. Each digit is on for 1 ms and the blanking time between digits is 100 uSec. The nixies are showing no ghosting at all. Any help in figuring out why my lamps are not turning fully off would be greatly appreciated. Schematics are attached. -- 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. To view this discussion on the web, visit https://groups.google.com/d/msg/neonixie-l/-/RssVX0Tgn2kJ. For more options, visit https://groups.google.com/groups/opt_out. -- 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 https://groups.google.com/groups/opt_out.