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A wireless relay for increasing receiving 

 speed and for relaying to telegraph lines 



Greater Speed in Wireless Receiving 



DR. RAY E. HALL, of Portland, 

 Ore., has recently developed an 

 invention that may increase the speed 

 of wireless receiving by automatically 

 recording at an average speed of a little 

 more than one hundred words a minute. 

 On test that speed has been increased to 

 as much as two hundred words a minute. 

 Speed, however, is not the greatest 

 factor in the invention, which is called 

 a wireless relay, for by means of this 

 device messages may be automatically 

 relayed to a wire telegraph line by the 

 same action which records the message. 

 This may easily open up new possibilities 

 for wireless telegraphy, by connecting it 

 directly to the wire system. The relay 

 may also be used for receiving a number 

 of wireless mcsssages at the same time, 

 on the same aerial at the same wave- 

 length. Relayed messages are auto- 

 matically written in ink, on commercial 

 ticker-tape. The ability to receive 

 simultaneously several messages is based 

 on tuning to spark-tone or group-fre- 

 quency instead of to wavelength only. 

 The relay is connected with the wire- 

 less set in place of orilinary telephones. 

 With the device a whole night's work 

 from Sayville, L. L, 1,500 miles away, 

 has been received at the experimental 

 laboratory. The instrument worked 

 alone in a room by itself, since it has 

 attached to it an automatic starting and 

 stopping de\'ice. When the wireless 

 message starts, the very first sound 

 transmitted is placed on record, and 



when the message is ended the tape 

 stops. 



A light current of air passing through 

 the box and coil into the cylinder 

 shown in the illustration, is the main 

 element employed in relaying the wire- 

 less signal. Any commercial record or 

 sounder, electric bell or light can be 

 attached to the instrument to record the 

 messages. 



Receiving Undamped Oscillations 



Arrange a piece of fine iron or steel 

 wire, such as that used for the "E" string 

 of a mandolin, over the pole faces of a 

 small horseshoe electromagnet of the 

 kind used in an ordinary buzzer. Mount 

 a contact-screw directly above the 

 wire where it passes across the magnet 

 faces. Connect the magnets in series 

 with an 8 c. p. lamp on the 60 or 120- 

 cycle alternating-current lighting line, 

 and put the iron wire and contact into 

 your receiving-circuit as shown in the 

 diagram. 



The arrangement in the accompany- 

 ing diagram gives a musical note to 

 the signals received from arc or high- 

 frecjuency alternator stations, the pitch 

 depending upon the number of cycles 

 used in the power line. The vibrating 

 wire much be adjusted so that the con- 

 tact makes a clean, sharp break each 

 time the lighting current pulls it down. 

 The tuner and detector must be adjusted 

 in the same way as for receiving spark- 

 stations. High-frequency spark-stations 

 can be heard while the wire-interrupter 

 is running, but the notes of their sparks 

 will be changed. 



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Diagram of a simple receiver for 

 undamped oscillations 



