TRANSISTOR BINARY PULSE REGENERATOR 



1079 



40 50 60 70 80 90 100 



IMPULSE AMPLITUDE AS PER CENT OF SIGNAL AMPLITUDE 



Fig. 8 — Repeater errors as a function of interference amplitude. 



On the other hand there are some deviations from the simple theory of a 

 perfect regenerator such as the low common threshold value of the plus 

 insertion and minus omission errors. Some of the differences can be 

 attributed to the extremely sensitive method of measuring errors. Here 

 the maladjustments of timing tank circuit, quantized feedback ampli- 

 tude as well as other factors which cannot be readily detected by other 

 means are reflected as sources of error. However with care these errors 

 can be made small and the measured values should follow the theoretical 

 values reasonably well. 



Most variations from theoretical values are due to changes in the 

 effective bias caused by intersymbol crosstalk. This can be demon- 

 strated by measurements made using set codes. In all these codes the 

 number of pulses equaled the number of blanks but combinations varied 

 from one to another. On Fig. 9 the omission errors are plotted for a 

 fixed impulse amplitude as a function of the nimiber of pulses which 



