High Frequency Apparatus Page 94

94 24 HIGH FREQUENCY APPARATUS 20 Woodwork 1 complete regd Fig. 10.-Woodwork for oscillation transformer scription herewith will accordingly be devoted to a discussion of the latter type only. With reference to Fig. 8, the base, 1, is of suitable dry wood as is also the upright support, 2. The dimensions and details of these parts are given in Fig. 10. The upright is secured to the base by means of stout brass screws passing up through the base. Upon the upright piece, 2, is mounted, on either side, the primary coil of the oscillation transformer. The complete coil is really two Oudin resonators placed base to base with primaries and secondaries in series. The details of the primaries are given in Fig. 11 and the reader will note that the primary conductor is of edgewise wound copper strip, held in suitable supports of fibre. These supports are detailed in Fig. 11 at 3. The secondary coils are of 400 turns each, of No. 30