DIRECT MEASUREMENT 



37 



CORRECTION 

 VOLTAGE. 



DETECTOR 



HF 

 OSCILLATOR 



AMP 



PHASE 

 DETECTOR 



4.5 MC 

 OSCILLATOR 



CRYSTAL 

 MODULATOR 



CAVITY 



Figure 2.9. The Deani expendable refradonieter {modified Pound oscillator). 



REFERENCE 

 CAPACITOR 



r 



- _r 



. ^ 



SWITCH 



OSCILLATOR 



DOUBLER 

 AMPLIFIER 



^ 



SENSING 

 CAPACITOR 



Figure 2.10. The Hay refradometer. 



