328 BELL SYSTEM TECHNICAL JOURNAL 



small distortion large currents whether used as an amplitier or modulator 

 or rectifier. It will be a poor voltage amplifier, detector or voltmeter. A 

 tube with a steep characteristic and large transconductance will be a good 

 voltage amplifier, detector or voltmeter, but will carry little current. 



Of course there are no rules without exception and special cases will be 

 found in practice where the above recommendations may be violated. 

 Electron tubes are used in many other ways than those discussed above and 

 the present analysis covers only a small part of the field. The methods of 

 computing modulation products shown above can be extended to triodes 

 with little or no modification in cases of modulator or rectifier design where 

 the external plate impedance is very low at the input frequencies. 



