. Practical wireless telegraphy; a complete text book for students of radio communication . ce with the aerial system discharges into the telephonecondenser, C-2 (Fig. 289), at regular intervals. Condenser C-2, in turn, discharges throughthe head telephone creating a single sound for the charge accumulated. Due to the factthat the tikker discharges C-1 at various potentials, or we might say, at different points onthe cycle of the incoming oscillations, a non-uniform note is produced lacking the desiredmusical pitch for reading through atmospheric electricity. However, the tikker suffices as as
. Practical wireless telegraphy; a complete text book for students of radio communication . ce with the aerial system discharges into the telephonecondenser, C-2 (Fig. 289), at regular intervals. Condenser C-2, in turn, discharges throughthe head telephone creating a single sound for the charge accumulated. Due to the factthat the tikker discharges C-1 at various potentials, or we might say, at different points onthe cycle of the incoming oscillations, a non-uniform note is produced lacking the desiredmusical pitch for reading through atmospheric electricity. However, the tikker suffices as asimple receiver and good results have been obtained by its use at several ship and shorestations. A favored form of circuit interrupter for the reception of undamped oscillations is thesliding wire or slipping contact detector, shown in Fig. 290. In the diagram a small brasswheel, W, mounted on the «haft of the motor, M, is in contact with the brush B ^— terminals of the slipping contact, B, Theare connected in the circuit of the tuner as the tikker, D, of Fig. 289. The cir- ^ - — D. Fig. 290—The Slipping Contact Detector for Reception of Undamped Oscillations. cuit is completedthrough the brush, B-1,in contact with the wheelW. When the wheel isin rotation, there is aconstant slipping andgripping of the brush Bon the wheel whichmakes a contact of vari-able resistance, causingthe charge accumulatedin the telephone con-denser to vary in ac-cordance. The note inthe telephone will havea pitch in the tikker andthe slipping contact de-tectors are considered as current operated devices, meaning that they function best in a tuning circuit whichaffords a maximum of current rather than a high voltage. The coils of the tuner for theseoscillation detectors are wound with Litsendraht wire or conductors of equal high frequencyconductivity. These detectors are applicable to the reception of damped oscillations or discontinuouswaves, but, owing to the discontinuity of the
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Keywords: ., bookcentury1900, bookdecade1910, booksubjecttelegra, bookyear1917
