A few months ago (on the recommendation of an old post by Mr. Hoffman) I bought a Fisher 500-c. Suffice it to say, I absolutely LOVE it. Steve also posted the following "instructions" that were given to him about using his new Fisher: "1. Power outlet: As you know these older devices do not come equipped with a plug that has the wider prong to identify it as being grounded. Nonetheless, it is important to pay attention to the orientation when you plug it in. The way to identify which way the plug goes in is by feeling the power cord. One side of the cord is completely curved and smooth on the outside while the other side of the cord has an edge. The side that is smooth should plug into the wider prong on your wall socket." I followed these instructions when I set up my Fisher, and everything works beautifully. So, if I understand correctly (according to these instructions), on the Fisher cord: The smooth side of the cord = wide prong = neutral & The ridged side = small prong = hot Here's my question, is this the STANDARD method of determining the hot & the neutral prongs on a vintage non-polarized two prong cord? In other words, does it apply to ALL cords? The reason I ask is that my 1964 Silvertone guitar amp has a non-polarized plug and it also has a "ridged" side and a smooth side running down the cord. BUT, I looked online and found a site about repairing a lamp cord that said the exact opposite! It said the RIDGED side of the wire feeds the wide prong (neutral side) & the smooth side is the hot side. I ALSO read somewhere that if one of the wires has printing on it, and the other does not, then that's usually the hot side. Does anyone have a definitive answer on this??? I apologize if this has been covered before... I know that the topic of flipping the cord around (reversing polarity) and getting a different sound HAS been covered in older posts. And I have found that to be 100% true. So thank you all for that.