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Voltage levels in Mesa 400+

To what degree if I may ask?
I'm not sure because I don't have the original build documents for the factory parts and there were more than one version from what we can all remember... at least 2 and maybe 3. I think the last version has an added pair of 100V taps, but not positive.

Even though these were dual primary, they were 120V ONLY when the primary is configured in parallel (must be parallel due to primary current versus wire gauge), but not so when used 220/230/240V. This is where the PCB configuration is not clear and none of us can remember... it's not obvious and we are all getting older too.