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Preferred Substitutes ......................... 12AX7 12DF7
Substitutes ................................... 12AD7 12BZ7
Source ........................................ ARRL HB - 1964
Source ........................................ ARRL HB - 1964
EIA Outline ................................... 6-2
EIA Base ...................................... 9A
Source ........................................ ARRL HB - 1964
Heater Voltage ................................ 6.3/12.6 V
Heater Current ................................ 0.3/0.15 A
Triode 1
Source ........................................ ARRL HB - 1964
Input ......................................... 1.6 pf
Output ........................................ 0.44 pf
Grid to Plate ................................. 1.7 pf
Triode 2
Source ........................................ ARRL HB - 1964
Input ......................................... 1.7 pf
Output ........................................ 0.4 pf
Grid to Plate ................................. 1.5 pf
Triode 1 Class A Amplifier
Source ........................................ ARRL HB - 1964
Plate Voltage ................................. 250 V
Grid No. 1 Voltage ............................ -2 V
Amplification Factor .......................... 100
Plate Resistance (approx) ..................... 62.5K Ω
Transconductance .............................. 1600 µ
Plate Current ................................. 1.2 mA
Triode 2 Class A Amplifier
Source ........................................ ARRL HB - 1964
Plate Voltage ................................. 250 V
Grid No. 1 Voltage ............................ -8.5 V
Amplification Factor .......................... 17
Plate Resistance (approx) ..................... 7.7K Ω
Transconductance .............................. 2200 µ
Plate Current ................................. 10.5 mA
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
Wed, 08 Feb 2023 23:32:50 -0700