PCF80

The PCF80 is a kind of triode pentode with seperate cathodes intended for use as frequency changer in television receivers.

What comes next is about the capacitances of PCF80: triode section (numbers denote pin number): (1)anode to all except grid (1-4+5+7+8), Ca(g): 1.8 pF; (2)grid to all except anode (9-4+5+7+8), Cg(a): 2.5 pF; (3)anode to grid, Cag: 1.5 pF; pentode section: anode to all except grid No.1, Ca(g1): 3.4 pF; (2)grid No.1 to all except anode, Cg1(a): 5.2 pF; (3)anode to grid No.1, Cag1: 0.025 pF max; between triode and pentode sections: (1)anode triode to grid No.1 pentode, CaTg1P: 0.16 pF max; (2)grid triode to anode pentode, CgTaP: 0.02 pF max; (3)anode triode to anode pentode, CaTaP: 0.07 pF max.

Then is about the typical characteristics of PCF80: triode section: (1)anode voltage, Va: 100 V; (2)grid voltage, Vg: -2 V; (3)anode current, Ia: 14 mA; (4)transconductance, S: 5 mA/V; (5)amplification factor, : 20; pentode section: (1)anode voltage, Va: 170 V; (2)grid No.2 voltage, Vg2: 170 V; (3)grid No.1 voltage, Vg1: -2 V; (4)anode current, Ia: 10 mA; (5)grid No.2 current, Ig2: 2.8 mA; (6)transconductance, S: 6.2 mA/V; (7)amplification factor, g2g1: 47.