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BELL SYSTEM TECHNICAL JOURNAL 



example, in the 1N26 unit, which was designed for use at frequencies in 

 the region of 24,000 megacycles, a small metal slug fitting over the central 

 conductor makes it possible to match a coaxial line having a 65-ohm surge 

 impedance. For certain circumstances this modification in design is 

 advantageous, while in others it is a disadvantage because the matching 

 slug is effective only over a narrow range of frequencies. 



IS 



POINT ASSEMBLY 



OUTER 

 CONDUCTORn 



METAL 

 DISC 



Fig. 6 — Shielded rectifier structure and parts. Overall length of assembled rectifier is 



approximately | inch. 



The shielded structure was developed in 1942 and since it was of a sim- 

 plified design with reduced hazard of static damage, it was proposed to the 

 Armed Services for standardization in June of that year. However, because 

 of the urgency of freezing the design of various radars and because the 

 British had aheady standardized on the outhne dimensions of the ceramic 

 type cartridge, Fig. 5, the Services did not consider it advantageous to 

 standardize the new structure when first proposed. In deference to this 

 international standardization program, plans for the manufacture of this 



'i 



