SILICOX CRYSTAL RECTIFIERS 



29 



INCREASING POWER-HANDLING ABILITY 



IN25 

 (14.7) 



IN2IB 

 (12.2) 



IN28 

 (13.2) 



IN26 

 (15.2) 



IN23B 

 (12.7) 



IN23A 

 (14.2) 



NEW PROCESS INTRODUCED 



IN2IA 

 (14.6) 



IN23 

 (17.1) 



SELECTION 



IN21 

 (16.4) 



— NOTE— I 

 NUMBERS IN PARENTHESES ARE 

 RECEIVER NOISE FIGURES IN 

 DECIBELS CALCULATED FOR THE 

 POOREST UNIT ACCEPTABLE UNDER 

 EACH SPECIFICATION AND BASED 

 ON AN INTERMEDIATE-FREOUENCy 

 AMPLIFIER NOISE FIGURE OF 5 

 DECIBELS ' 



24,000 



FREQUENCY IN MEGACYCLES PER SECOND 



Fig. 17 — Evolution of coded silicon crystal rectifiers. 



1942 1943 1944 1945 * 



YEAR 

 Fig. 18 — Relative annual production of silicon crystal rectifiers at the 

 Western Electric Company 1942-1945. 



affirmative. The importance of this decision may be appreciated from the 

 fact that it permitted the coding and manufacture of units such as the 1X2 IB 

 and 1N28, high burnout units with improved performance at 3000 



