A HIGH PRECISION STANDARD OF FREQUENCY 



^ - ^ + f + ^ ^ 1,000 ( f^ +/^ t/3 +f^ _f^) , 



^ _ a-hb + c ^ j^QQQ I - ^^ ' •'■' :-"''' - /2 ) , 



c - "^ + ? "^ "^ = 1,000 ( '''''' \ '' ' -'' -h ) , 



"^ + f + ^ = 1,000 ( - ^^ ' ''' y ' '' - /4 ) . 



509 

 (8) 



(9) 

 (10) 



(11) 



Fig. 17 — Four 100,000-cycle oscillators with auxiliary equipment. 



The four oscillators used in the equipment described are shown in 

 Fig. 17. The panels on which the controlling and measuring circuits 

 are mounted are at the right of the picture. The 1,000-cycle motor- 

 driven clock is at the top of the nearest panel. A schematic of the 

 apparatus showing the general arrangement of parts is given in 

 Fig. 18. 



