Say I need an AC transformer that outputs something like 20-0-20 (give or take a few volts). Toroidal transformers are quite expensive. Laminated steel core transformers are affordable, but I can't find any that have a 0v line. Can I just wire the zero volt to earth?

I've been eyeing these "DIY" 2.1 Channel TDA7294 2x80W+160W power amplifier kits. I have a 19.0V - 0v - 19.0V toroidal, but a match there is not. So, I'm trying to figure out what I need & I've been banging my head against the wall for about a week now.

Any recommendations, other than therapy?

 

What is meant can't find a 0V line? This is just a centre tap of a 40v continuous winding.
What is the problem with the 19-0-19? If it measures 38v across the outer ends then it is centre tapped.
Max.

 

Many power transformers come with C.T. (center tap) secondaries. That is what the 20-0-20 means.

The center tap is simply your 0V reference or common.

 

Center-Tapped! Thank you both! For this most arcane of jargons, I am forever in your debt.

 

You're welcome. You just have to ask. Someone here will have an answer.
Welcome to AAC!