PRESPJNT STATUS OF TRANSISTOR DEVKLOPMENT 



429 



Fig. 20 — Tentative characteristics for the M1689 switching transistor. 



Fig. 21 — -Reliabilit}' status. 



RELIABILITY STATUS 



Life 



Reliabilit}^ figures of merit are not too well defined for electron tubes 

 and the same situation certainly holds at present for transistors. How- 

 ever, insofar as these quantities can be presently defined, Fig. 21 shows 



