Note: Please do not link down into my pages. I change this directory structure often and your links will not work correctly.
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Preferred Substitutes ......................... 4X250B
EIA Base ...................................... F75
Heater Voltage ................................ 6 V
Heater Current ................................ 2.1 A
Tetrode
Input ......................................... 18.5 pf
Output ........................................ 4.7 pf
Grid to Plate ................................. 0.04 pf
Tetrode
Plate Voltage ................................. 2000 V
Grid No. 2 Voltage ............................ 400 V
Plate Dissipation ............................. 250 W
Grid No. 2 Dissipation ........................ 12 W
Class C Oscillator/Amplifier
Plate Voltage ................................. 2000 V
Grid No. 2 Voltage ............................ 250 V
Grid No. 1 Voltage ............................ -90 V
Grid No. 1 Current ............................ 27 mA
Plate Current ................................. 250 mA
Grid No. 2 Current ............................ 25 mA
Driving Power ................................. 2.8 W
Power Output (approx) ......................... 410 W
Class C Modulated Amplifier (Plate)
Plate Voltage ................................. 1500 V
Grid No. 2 Voltage ............................ 250 V
Grid No. 1 Voltage ............................ -100 V
Grid No. 1 Current ............................ 17 mA
Plate Current ................................. 200 mA
Grid No. 2 Current ............................ 25 mA
Driving Power ................................. 2.1 W
Power Output (approx) ......................... 250 W
Push Pull Class AB1 Amplifier
Plate Voltage ................................. 2000 V
Grid No. 2 Voltage ............................ 350 V
Grid No. 1 Voltage ............................ -50 V
Peak Grid No. 1 Voltage........................ 100 V
Plate Current ................................. 500 mA
Grid No. 2 Current ............................ 30 mA
Driving Power ................................. 0 W
Load Resistance ............................... 8.26K Ω
Power Output (approx) ......................... 650 W
If you are uncertain about the EIA designator for a particular tube please use the "Index" button to list all the tubes in the database. You can click on the designator for the closest tube.
(c) 1994-2021 by William A. Beech, NJ7P
Mon, 06 Feb 2023 17:56:31 -0700