NEGATIVE-GRID VACUUM TUBES 



583 



Ip+Ig Vc=0 



r-p ip 



FIGURE 9 



Vc = 



Fig. 8 — Equivalent network of vacuum tube from equations (1) and (2). 



Fig. 9— Relation between currents of delta network and those of Fig. 8. 



Fig. 10 — Equivalent delta network. 



Fig. 11 — Equivalent cathode-plate paths. 



Fig. 12— Modified delta network equivalent to Fig. 10. 



