ZM1177 with hexagonal grid - counterfeit NIXIE tube?

[ten kowal]

Long story short, I came across a seller offering scraps from some lab equipment. The thing that was most interesting is that the seller claimed, that the tubes were Z574M and ZM1177, while all of them looked similar - like Z574M with or without red paint. They are on same boards with pinout looking in same way. 

When asked, he (she) sent me attached photos.

The tube looks just like Z5740M, and the marking looks very unproffesional. 

Do you think it is possible that someone was actually removing paint and printing wrong labels years ago? I don't think this seller would do that, he did not include word "NIXIE" anywhere in his original offer.

[MichaelS]

Check out nocrotec.com for more info on these tubes.  They all look ike zm57-series tubes which came with clear or tinted glass.

I've heard that some companies bought unlabeled tubes in bulk and resold them with their own labels.  That may explain the zm1177 markings.  1177 tubes have 15.5 mm digits and use 2.5 ma versus 13 mm & 2 ma for the 57x tubes.  The digit size difference is noticeable.

Interesting find though.

[ten kowal]

I think that they have to be Z57xM. I found an easy way to tell if a tube is RFT made or not - RFT made rounder digits, and number 6 is the easiest to see. Every other tube I have seen has 6 consisting of a circle and a straight line, while RFT tubes have 6 made of a circle and a curve. 

On photos provided by the seller we can clearly see the curvy 6.

By the way, does anyone know where those panels might come from? It is not the first time I'm seeing Z57xM display cosisting of vertical PCBs with single tube.

[ten kowal]

Well, not every other tube has straight 6. But every other tube has significantly different style of that digit.