output voltages ranging from 012V, 5Amp R-core Transformers are manufactured using the unique rectangular core with round cross section known as R-core. The special feature of this transformer is that the core is gap less and continuous. The winding is done on special round bobbins on two parallel legs of the core. Design The core is continuous and gapless, with two balanced windings on either side. The winding is done on special round bobbins on the two parallel legs of the core. Size R-core transformers are smaller and have a lower profile than E-I core transformers of the same capacity. Temperature rise R-core transformers have a lower temperature rise due to the round cross sectional area and tapered slitting. Noise R-core transformers have low noise due to the balanced winding and low flux leakage. This makes them suitable for use in noise sensitive equipments. Leakage flux R-core transformers have a leakage flux that is about 1/10th of conventional transformers. This allows the transformer to be placed close to critical electronic components.