IN-13 Burn-in

[Willsor]

Hi Guys,

I have some IN-13 nixie bargraph tubes, and they arent reaching the top of the display for ~5mA. As I understand it, these tubes need to be burnt-in before operation to make them behave and reach the top correctly. 

I tried burning the tubes in with 10mA at around 120V for around 10 minutes to no avail.. the maximum achievable length didn't seem to change.

 The main reason I didn't want to do this for longer or at higher current was for fear of damaging them. Should I try burning them in again?

How easy is it to break these things with overcurrent?

Cheers

[marta_kson]

Are You sure You have connected the tube correctly? It's possible to reverse the anode and auxilliary cathode and it apperars tp work, but with a very high current needed for full scale "deflection". Under those conditions, the tube burns out quite fast.

There is a thread about that in this group, titled IN-13 Lifespan

Maybe the link below will work.

https://groups.google.com/forum/?hl=en#!topic/neonixie-l/PxAF6WguXg4

[Willsor]

Sorry for the slow reply!

Yes I have double checked all the connections and they are correct.

I may try to burn them in again with a slightly higher current.

[Paul Andrews]

There is an article about IN-13 tubes here: https://www.saltechips.com/lab/the-parasitic-current-leakage-mechanism-of-the-in-13-tube/. The whole site is dedicated to those tubes. It is very interesting reading for anyone interested in how Nixie tubes work.

[Tomasz Kowalczyk]

This is very interesting. Do you know (or does anybody know) if the same applies to IN-9?

[gregebert]

IN-9's are 2-terminal devices, so they are not quite the same. However, there could be a similar mechanism that impairs their performance.

My limited experience with  IN-9's is that they can behave erratically, such as not fully illuminating at rated max-current (even at 2X, I only got about 80% illumination), and they will sometimes dim from the opposite direction when the current is reduced (normally, glow moves bottom-to top when current increased, then top-to-bottom when current is decreased. I've had random cases where they dim bottom-to-top instead).

IN-9's definitely work much better with a current-controlled source. As long as I keep mine under 50% illuminated, they had fairly linear, and consistently monotonic, behavior. When I crank them towards 75% illumination or more, the weird things happened.

Also, I found that poorly filtered DC supply, with a series resistor, caused even more erratic behavior versus current-controlled supply. I actually gave up on these things 5+ years ago because I incorrectly concluded they were too unpredictable.

I'll see if I can run one of mine for more hours, until it shows problems, then open it up.