High Frequency Apparatus Page 124

124 HIGH FREQUENCY APPARATUS THIS CORE FOR 25, 60 OR 125 CYCLES ASSEMBLY PRIMARY CYCLES 25 400 TURNS NO.12 D.C.C. SECONDARY 16800 Tu NO. 30 EN 60 200 TURNS 83400 Tu NO. 11 D.C.C. NO. 28 EN. 125 100 TURNS NO. 11 D.C.C. 4200 Tu NO. 23 EN. Fig. 2. Data for the magnetic leakage transformer The 2 x 54 in. pieces of steel are to be divided into two equal piles and each pile assembled with the strips alternating to such an extent that the overlap is just 2 in. The assembled pieces may be clamped in a vise and tightly bound from end to end with friction tape, releasing the core an inch at a time as the binding proceeds. The winding is done directly upon the core in the case of both primary and secondary. The illustration suggests how this may be accomplished. Two blocks of wood are prepared with recesses to take the ends of the core strips in order that the core may be held in the lathe for winding. The primary winding consists of 200 turns in all of No. 11 D.C.C. wire tapped at 110, 140, 170 and 200 turns. The winding is 27 turns per layer and the first layer of wire is wound upon two thicknesses of micanite wrapped