Sizing transformer for custom made neon light


New Member
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.


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New Member

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?

Johnny Best

Active Member
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.


This thing is a little terrifying. Tell me there is a cover for the top set of electrodes that we aren't seeing?
But really, find a glass bender and show him the transformer, he will tell you exactly what it is, and hopefully just mark it up a little to sell it to you.

Here is an interesting find on Amazon for 'frequently bought together.' Looks like the mob has been frequenting amazon for their torture setups...