Nixie Clock Build GN-4, Proximity Sensor, GPS & Dekatron

Yes, I think the best thing is to build a kit and see how it goes. Many people decide after their first kit that they really like doing this stuff and go on to delve deeper into the design and theory.

Ian's stuff is open source, so you can check it out as much as you want before making any decisions. Manuals, schematics, code, etc. are all here:
www.nixieclock.biz/Manuals.html
Scroll down a ways to find Classic Rev. 6.

To be clear: I'm steering you toward the Classic because that board does not care what the pin arrangement of your tubes is (Modular and All-In-One are for specific tubes). and Rev. 6 because of the spare outputs that are available only on that version. Classic works with all tubes designed for ~170V (that would be most every Nixie made, including GN-4) as long as they are not biquinary (GN-4 is not).

I don't have a specific plan for the Dekatron. It will take some creativity but it can be done. Dekatrons are not my forte but I do know there are Dekatron "spinner" circuits and even some kits online. My general plan would be to use a spare output on the clock to trigger the Dekatron spinner to spin once per second, or perhaps pulse it 10 times per second to "step" it. The clock code would require additions to control the output and the spinner circuit might need some mods too. It shouldn't be super complicated, but it's not something I can bang out off the top of my head in a forum post either. Do be aware that you need to use a clock kit that is open source so you can modify the code.

Yes all Ian's designs cycle the digits to prevent cathode poisoning. It might be called "ACP" in the docs.

I can't find it on the store page, but the motion sensor (PIR) is an option that has to be specified when ordering. If you decide to buy a kit I recommend contacting Ian directly via the contact link on the store site. He can get you sorted out on what exactly you need to order to get the functionality you want.

Thanks for that!

Just add a note to the order and I will put in a suitable microwave sensor. I think I have to gte another batch, my box seems to be getting empty.

Mike, 1 other thing here... you got me thinking about Dekatron tubes so I went looking around and found this:
threeneurons.wordpress.com/dekatron-stuf...ekatron-spinner-kit/
Yes it's a spinner, whereas you would want more of a stepper, but if you scroll down almost to the bottom of the page he shows an example of how to make it into a stepper. All you would have to do is add code to pulse a spare output 10 times per second of you want your Dekatron to go "once around the dial" every second. Maybe also tap off one Dekatron cathode to get a "top dead center" type input for the purpose of initializing it to always start in the same position.

I'd add opto-isolators for extra assurance that the 450V Dekatron supply can't end up getting into the clock controller.

I have no idea if he still sells the kit or not but the full schematic and parts list is there on the web page for you to freely copy if you felt so inclined.