Dave,

Modern Welding Technology by Howard B Cary,

Get it new, Get it used, Get it!

It will be about 35 bucks but well worth the investment.

It will answer prolly every question you have put to the forum and you won't be so distracted by bad advice and hotheads.

The forum is nice but don't melt metal or spend a cent before you have hard copy trustworthy data to help with your decisions.

It would just take too long to explain with good detail the differences between constant voltage and drooping voltage power sources. Nonetheless take heart! you are asking ALL THE RIGHT QUESTIONS.

Lawrence
Welding Instructor
United Airlines