Reference Transformers

I didn’t find any transformer on the local market to be used as reference which could give me some confidence. Especially after reading about the phase shift and the behaviour of standard transformers, I couldn’t select any ready available in my country. So I decided to build a couple of them for my own use.
I ended up with some good result.
Phase shift close to 0. Can be used for both 230V and 110 V input adding a centre tap which is not there now but easy to add.
The result looks good to me. What do you think?

Phase shift is typically in the range of 0 to 3 degrees (166us) so I don’t think it would show up there.

That said, you can probably just use about 1 degree of shift and get satisfactory results.

Thanks for your comment. The shift is 53us and 49us. It shows up in the bottom right. So, it should be less than 1 degree.