. The Bell System technical journal . GMT IE PU 12 AM 12 12 PM 12 AM e 12 PM 12 AM B. K. PM 12 F«b. S2-25 S«pU 23-24 Jan. 27-28 Oct. ft- 25-26 JO-Oct. I F»b. 1- 12 12 PM 12 AM IZ 1924 1 livlurcriul afte lagnctic storm had !>cgiin. IiR. —Correlation I>ctwccn radio transmission and variations in earthsniadndir field Diiiniul Vdrialion. An )le of llie diurnal characteristic ofthe noise for both ends of the transatlantic path is given in Fig. curve is shown for each of the several frecjuencics outstanding points to be observed are: 1. The rise of the static noise
. The Bell System technical journal . GMT IE PU 12 AM 12 12 PM 12 AM e 12 PM 12 AM B. K. PM 12 F«b. S2-25 S«pU 23-24 Jan. 27-28 Oct. ft- 25-26 JO-Oct. I F»b. 1- 12 12 PM 12 AM IZ 1924 1 livlurcriul afte lagnctic storm had !>cgiin. IiR. —Correlation I>ctwccn radio transmission and variations in earthsniadndir field Diiiniul Vdrialion. An )le of llie diurnal characteristic ofthe noise for both ends of the transatlantic path is given in Fig. curve is shown for each of the several frecjuencics outstanding points to be observed are: 1. The rise of the static noise about the time of sunset at the receiv-ing station, the high \ at night, and the rather sharpdecrease accompan_\ing sunrise. The curve for 15 kc. shows the ex-istence of high \alues also in the afternoon. During the summermonths higii afternoon values are usual for all fretiuencies in this I :ril<)\l. I 477. , - JD •\ ^* ^K--. ^ ^• C-- Y 5 SI yn. *»^ ■Nr >«, .^-^ \ X^^N ;^» \ \ ^■c Die .«..^_ \ \ ^: » \ ^--^ -. a K \, ^ w^ AUS.^ s \ *«. FCR ItU ^^ ■^ OB t. J<NC».KI .OCTO-ES 1 ^ 0 } 0 : M Fig. 15 —Fre(|ucncy distribution of noise, New Southgatc, EiiKlaiidNight time Day time 1923-1924 478 BELL SYSTEM TECHNICAL JOURNAL range. Thiy rxtcnd later into the fall for the lower fretiiiencies, andhence arc in e\idence on the date mi which these measurementswere taken, October-November. 2. In genera! the noise is greater the lower the frequency. Noise as a Function of Frequency and of Receiving Location. Thedistribution of static noise in the frequency range under consider-ation is depicted in Fig. 15 for the case of reception at New Southgate,England. The set of full-line curves is for daylight reception and theset of dash-line curves for night-time reception. The values obtainingduring the transition period between day and nigh
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
