B9A Nixie Tube Tester & Regenerator

October, 17th 2005:

This little Project was necessary to test and regenerate a large lot of Nixie tubes with B9A base I bought some weeks ago. As you know all B9A Nixie tubes are biquinary tubes.
After the schematic of the clock was finished I sketched the schematic of the tester, which used the same conditions as they are in the clocks I built.
This was the final version of the schematic:

The Tester was built to test the following tubes:


You can view the data of these tubes here.

For normal the ZM1030 and ZM1032 tubes only have to be tested, because they contain mercury and do not show any cathode poisoning.
The problematic types are the B-5025 and the NL-5025.
These contain no mercury and get much cathode poisoning if they are operated in one digit state only.
So these types (B-5025 and NL-5025) must be tested and regenerated.

If you want to know more about cathode poisoning and how to remove it, click here.

This picture shows the regenerator in action:

There are some features in the tester, which I don't want to explain in detail.
The over- current is adjusted by the power supply (not shown in the schematic)
The digits are switched through automatically.
The time is adjustable, or can be set to infinity.
After the time has elapsed, the tester stops and the buzzer beeps.
If the tubes still show cathode poisoning, the regenerator has to be started again.

So I tested and regenerated about 2000 Nixie tubes....
Here some pictures of a clock using the tubes.

Thanks for reading!

Back to Dieter's Nixie Tube Page

eMail to Dieter