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BELL SYSTEM TECHNICAL JOURNAL 



Fig. 5 shows transient effects of a 600-mile composited 19-gage H-174 

 side circuit. The zero lines of the three curves of this figure show slight 

 effects of crosstalk and other interference. These effects are not, how- 

 ever, of sufficient magnitude to interfere with the general appearance 

 of the signals. The upper line shows the applied 1,000-cycle current. 



Fig. 4 — Transients in 174 sections of high-pass filter (cutoff frequency 107 cycles). 

 Upper trace— transmitted 200-cycle wave with harmonics obtained from an over- 

 loaded amplifier. Lower trace — received wave. 



The next line shows the current as it was received at the end of the 

 line. The transients which are produced at the beginning and ending 

 of the signals are evident. 



By the insertion of proper networks it is possible to correct for dis- 

 tortions of this kind. In the last line there is shown the received cur- 



Fig. 5 — Correction of transients in 600 miles of medium heavy loaded cable circuit 

 through use of delay correcting network. Upper trace — transmitted 1000-cycle 

 wave. Middle trace — wave received from line and applied to delay correcting 

 network. Lower trace — wave received from delay correcting network. 



rent when a delay correcting network of this kind is applied in series 

 with the circuit. It should be noted that while the delay in the recep- 

 tion of the signal is somewhat increased (as shown by the displacement 



