Re: Neon sign transformers...

> Is it safe to series connect neon sign transformers?

It's probably safe, but it won't do anything for you.  Neon sign 
transformers secondaries are center-tap grounded.

> How about parallel, to get more than 30ma?

That you can do.  Just use transformers with the same voltage 
ratings and make sure they're in phase (if you can draw an arc from 
one xformer to the other between the terminals you're going to wire 
together, they're not in phase and you have to reverse the primary 
wires on one xformer, or switch the HV wire from one transformer to 
connect to the other HV side of the other transformer).

Steven Roys (sroys-at-radiology.ab.umd.edu)