ARRANGEMENT FILTER LOSS CHARACTERISTIC 



BLOCK DIAGRAM OF ARRANGEMENT 



MODULATOR r 



SAME AS ABOVE 



WITH LOSS CHARACTERISTIC PER 

 CURVE A OF FIG. I, Af = 35^^ 



WITH LOSS CHARACTERISTIC PER 

 CURVE B OF FIG,l,Af = 70~ 



fs = SPACING FREQUENCY 



fm= MARKING FREQUENCY 



OSCILLATOR 



ZI 



MODULATOR 



NOS PER CURVE C 



HSP-a 



^ 



r 



Fig. 2 — Telegraph arrangements tested. 



