Sizing transformer for custom made neon light

[Dellview1996]

I have a friend who got a custom made neon sign/sculpture and the transformers have gone bad. Unfortunately the two transformer are very old so there is no labeling on what their voltage output was. How can i determine how many volts I need? I don’t want to have too much voltage and damage it. Each transformer controlled 10 of the bulbs, (20 total). The second transformer that is on in the picture partially works but flickers and must also be replaced.

 

[Dellview1996]

Here are some higher quality photos, the first uploads aren't very clear. The bulb sockets say TRANSCO Heat Resisting Houstin CAT. TC-50, 7500 volts. Is a 7500 volt transformer what I need? or is it different since the bulbs are hooked up in series?

 

[Z SIGNS]

You need a tube footage chart.
here https://www.nepcosignsupply.com/FootageCharts/AllansonTransFootageChart.pdf
You use this by knowing the diameter, length and type of gas each tube been filled with.

 

[Johnny Best]

I use to measure the lenght of the neon and find the transformer that fit the size and get the next size up from that to be on the safe side. Transformers must have changed since I changed one out so find an electrical company that sells them and get info from them on what size. Be careful with neon transformers and electricity, it can put you down for good.