. Practical wireless telegraphy; a complete text book for students of radio communication . densers, a slight change in capacitanceshould be made. RECEIVING CIRCUITS, DETECTORS, TUNING APPARATUS. 177 (a) It should be remembered in adjusting a station for the first time that the adjust-ments of any given tuner will vary with different aerials. If the tuner is alsostrange to the operator, the best method to pursue is to tune first to the standard 600meter wave, using a rather large amount of inductance and relying upon the seriescondenser to vary the antennai wave length to pick up signals, ther
. Practical wireless telegraphy; a complete text book for students of radio communication . densers, a slight change in capacitanceshould be made. RECEIVING CIRCUITS, DETECTORS, TUNING APPARATUS. 177 (a) It should be remembered in adjusting a station for the first time that the adjust-ments of any given tuner will vary with different aerials. If the tuner is alsostrange to the operator, the best method to pursue is to tune first to the standard 600meter wave, using a rather large amount of inductance and relying upon the seriescondenser to vary the antennai wave length to pick up signals, thereafter reducing theinductance and eliminating the short wave condenser until the maximum strength ofsignals is obtained. (b) If a call is expected from one of several wireless stations not accurately tunedto tile same vyave length, close coupling should be employed between the primary andsecondary windings and the shimt secondary condenser set at zero, but. after communi-cation is established, lesser values of coupling should be employed to preventinterference. (See Section H appendix.). Fig. 203b—Rear View of Marconi Type 112 Receiving Tuner (The American Marconi Company). (c) Due to the fact that the wave length of the average ships aerial lies between300 and 600 meters, only a few turns of inductance are required to adjust the antennasystem to the wave length of 600 meters. On the other hand, the short wave variablecondenser must invariably be employed to obtain the 300 meter wave with a shipsaerial. (d) If the tuner is fitted with a primary shunt condenser, increased selectivity maybe obtained by proper selection of capacity values, but generally with decreasedstrength of signals. (e) Severe discharges of atmospheric electricity may temporarily or permanentlydestroy the sensitiveness of a receiving detector, hence frequent readjustment is neces-sary during an operating schedule. These remarks^ however, do not apply to a highlyexhausted three-element vacuum valve, the magn
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Keywords: ., bookcentury1900, bookdecade1910, booksubjecttelegra, bookyear1917
