Vigortronix 230v toroidal transformers single primary dual secondary vigortronix vtx 146 120 125 toroidal transformer open style 120va 230v ac primary winding 2x 0 25v ac secondary windings 150mm lead length ul csa tuv en60950en60065 compliant vigortronix vtx 146 120 125 toroidal transformer 230v single primary 120va 0 25v