Quoted from snakesnsparklers:
Has anybody ever had only half of the sign turn on when you initially power it up? Happens to me sometimes and usually if I just switch it back off and on it works great. I am wondering if this is an issue with the sign, or due to how I power it up concurrently with multiple games on the same switch.
Could be as simple as taking the electrode boots off and seeing if the leads have a lot of paint on them, If there is then its not making a good connection! Take the boots off and just by using your fingernails strip the paint off the leads!
If that doesn't work then it is a little more of an issue like either a bad tube or power supply! You have to keep in mind these signs are cheaper in price due to the fact that they're made using cheaper products (neon tube is smaller, power supplies are cheaper and not UL approved). Not knocking the signs as they're cost effective but just don't expect to get the use out of them that you would a "commercial" neon sign!