ANALYZER FOR COMPLEX ELECTRIC WAVES 247 



tion. The most frequent use of the ampUfier in the laboratory has 

 been in measuring voltages around 10~'- volts but it can also be equally 

 well used to measure much smaller values, of the order of 10~^ volts, 

 when the frequency employed does not make the input impedance of 

 the first tube too low. 



In the choice and arrangement of the elements of this system and 

 for many of the details of its adjustment recognition is particularly 

 due to the extensive contributions of E. Peterson, W. A. Mueller and 

 C. R. Keith. 



