I h'.tw.ii I .i.Mic K.inio n.i.i.i'iiosr. i u.ixsmissiox -vks 



iransiniittT. Morr rt'cently a proKrain of consisti-nt (>l)st'rvalii)ns 

 in iliriTtional n-ci-ption of east-to-wi-st traiisiiiission was also undcr- 

 taktn in whiili were oniployi'd, wave anti-nnai- hiiilt by the F<a(lio 

 Corporation of America for radio tt-Ii-graph o[HTatinn upon lower 

 freqiUMicii-s. 



An indication of llu- inipni\cnu'ni which ilu- w.i\c antenna >{i\'es 

 in signal-to-noise ratio is had 1>\ reference lo l-'ii;. 2S. Thi- set of 



\» («S>U I n>c»r> 



2KS (S7K^ aacovaa «t 



-A.i>ftV^ 



Fig. 28 — Improvement in sij;nal noise ratio of wave antenna over loop reception 



curves to the right is for reception at Chedzcn', England, and those 

 at the left for reception at Belfast and Riverhead in the linited 

 States. The improvement is measured in terms of the signal-to- 

 noise ratio obtained on the wave antenna, divided h\' the signal-to- 

 noise ratio measured on the loop. For the particular days and fre- 

 C4uency indicated, the improvement in England will he seen to vary 

 over a considerable range, averaging about 5. Data for reception 

 in England is for 1024 while that for the Ignited States is for the 

 corresponding period of 1925. The Tniled States results will be seen 

 to be generally similar to those obtained in England. .Although 

 these experiments are still in an early stage, the results do give a 

 measure of the order of imprf)vement which can be expected. 



Tesl of Words I'nderslood. Perhaps the most convincing measure 

 of the efficiency of directional recei\ing systems for transatlantic 



