NEGATIVE-GRID TRIODE OSCILLATOR AND AMPLIFIER 573 



pentode of similar rating. A four-stage amplifier employing the inter- 

 mediate tube gave comparable results and although experimental data 

 are not yet available, it seems reasonable to assume that the small size 

 tube will permit of stable operation as an amplifier at frequencies as 

 high as 1000 megacycles. 



The double-lead tube is therefore seen to possess a number of distinct 

 advantages, both as oscillator and as amplifier, in the frequency range 

 from 100 megacycles to 1000 megacycles. While the ultimate limit to 

 which such developments may be pushed is still a matter of conjure it 

 seems safe to predict that the triode will be able to meet the demands of 

 the circuit designer at least for some time to come. 



