pcl 805 pentode power out put , SE amp.
Vg2 210V
RL = OPT = 4.4K
Vp 220V, Ia 30mA, Vg1 -22V
จากกราฟ
Ig2 5mA
Ik = 30+5 = 35mA
Rk = 22V/35mA = 628R/0.8W = 620R/5W
B1+ = 22+220+10 = 242+10 = 252V
Vp gnd. 242V
Rg2 = 252-210V/5mA = 42/5 = 8.4K/0.2W = 8.2K/5W
Gm = 44-21mA/24-20V = 23/4 = 5.75mA/V
Rk' = 1/Gm = 1/5.75m = 174R
Zk = Rk'//Rk = 620R//174R = 107880/794 = 136R
Ck = 1/2*3.14*10*136 = 1/8541 = 117uF
ได้กำลังประมาณ 3W