84 



THE BELL SYSTEM TECHNICAL JOURNAL, JANUARY 1956 



INPUT LEVEL 



Fig. 15C — Resultant output with differential bias. 



BRANCH 2 

 BRANCH 1 



RESULTANT 



INPUT LEVEL 



Fig. 15D — Characteristics of the separate branches and resultant output with 

 equal biases. 



of peak pulse amplitude — then at the output of the slicer there will be 

 no effect whatsoever from disturbances unless these disturbances exceed 

 half of the pulse amplitude. It is this slicing action which removes the 

 amplitude effects of noise. Time jitter effects are removed by retiming, 

 i.e., the device is made to have high loss regardless of input level except 

 at those times when a gating pulse is present. 



Fig. 15A shows schematically a low-frequency equivalent of the re- 

 generator used in these experiments. Here an input line divides into two 

 identical branches isolated from each other and each with a diode shunted 

 across it. The outputs of the two branches are recombined through neces- 

 sary isolators to form a single output. The phase of one branch is re- 

 versed before recombination, so that the final output is the difference 

 between the two individual outputs. 



Fig. 15B shows the input-output characteristics of the two branches 

 when the diodes are biased back to be non-conducting by means of bias 

 voltages Vi and V2 respectively. For low levels the input-output char- 

 acteristic of both branches will be linear and have a 45° slope. As soon 



