IANAEE (electrical engineer), but I do some antique radio collecting. When you work with computers, memory chips, all that, your instinct is to be grounded. I r

IANAEE (electrical engineer), but I do some antique radio collecting. When you work with computers, memory chips, all that, your instinct is to be grounded. I read that the opposite is true when working on old radios. When you're ground, you can get all of 110 volts going through you. From the "All American Five" wikipedia page, "The standard line up of tubes were designed so that the total rated voltage of the five tubes was 121 volts, slightly more than the electricity supply voltage of 110-117V. An extra dropper resistor was therefore not required. Transformerless designs had a metal chassis connected to one side of the power line, which was a dangerous electric shock hazard and required a thoroughly insulated cabinet." An isolation transformer is your friend if you work on them.