Let me begin by saying that I am a hobbyist, and I've been stupid with transformers before and I'm fed up with that. This question doesn't have to do with design so much as just not killing myself, so I hope this is the right place.
I have a step-down transformer with no external wiring to allow it to easily interface with mains or a load. The transformer is salvaged from nonfunctional equipment, I have confirmed continuity between each secondary tap and continuity between primary taps, and discontinuity between the primary and secondary. I don't know anything about the ratio between primary and secondary windings.
Is there a non-hacky (but preferably time-saving) way to measure the secondary voltages?