How can I tell if my output transformer is live or dead?
There are some simple tests you can run to quickly determine if a transformer is grossly bad. This is much simpler than determining if it will work well and sound “good” for you. The tests of relative “goodness” are also possible, but require a lot of equipment and experience to do correctly. For the quick and dirty tests described here, you’ll need a means of measuring AC voltage and current simultaneously, such as a pair of VOMs or DMMs, and a 110/120 to 6.3VCT filament transformer, and either a variac (variable transformer) or a light bulb socket in series with the primary of the filament transformer to limit the power you put into the transformer under test.
