UCH81

The UCH81 is designed as one kind of triode-heptode. Heptode section intended for use as mixer RF of IF amplifier. Triode section intended for use as oscillator in AM/FM receivers.

Some limiting ratings and absolute maximum ratings of UCH81 have been concluded into several points as follow. (1)For the heptode section its anode voltage would be max 550V for Va0 and would be max 250V for Va. (2)Its anode dissipation would be max 1.8W. (3)Its grids No.2 and 4 voltage would be max 550V for Vg2+4o and would be max 125V for Vg2+4. (4)Its grids No.2 and 4 voltage (Ia max 1mA) would be max 250V. (5)Its grids No.2 and 4 dissipation would be max 1W. (6)Its cathode current would be max 18mA. (7)Its grid No.1 resistor would be max 3Mohms. (8)Its grid No.3 resistor would be max 20kohms. (9)Its grid No.3 resistor directly connected to grid triode would be max 3Mohms. (10)Its cathode to heater voltage would be max 100V. (11)For triode section its anode voltage would be max 550V for Va0 and would be max 250V for Va. (12)Its anode dissipation would be max 0.8W. (13)Its grid resistor would be max 3Mohms. (14)Its cathode current would be max 6.5mA. (15)Its cathode to heater voltage would be max 100V. It should be noted that stresses above those listed in absolute maximum ratings may cause permanent damage to device.

Also some typical characteristics of UCH81 are concluded as follow. (1)For triode section its anode voltage would be 100V. (2)Its grid voltage would be 0V. (3)Its anode current would be 13.5mA. (4)Its transconductance would be 3.7mA/V. (5)Its amplification factor would be 22. (6)For the heptode section its anode voltage would be 160V. (7)Its grid No.3 voltage would be 0V. (8)Its grids No.2 and 4 voltage would be 90V. (9)Its grid No.1 current would be 0.5uA. (10)Its grid No.1 voltage would be -0.5V. And so on. If you have any question or suggestion or want to know more information please contact us for details. Thank you!