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Substitutes ................................... 56
Source ........................................ RCA R-10 - 1932
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Substitutes ................................... 56
Source ........................................ RCA RC-11 - 1933
Source ........................................ RCA R-10 - 1932
The '27 is a three-electrode general purpose tube containing a 2.5 volt heater-cathode of the equi-potential type which permits operation from alternating current.
Source ........................................ RCA R-10 - 1932
Bulb .......................................... S-14
Base Type ..................................... Medium 5-Pin
EIA Outline ................................... 14-0
Maximum Overall Height ........................ 4-11/15 In.
Maximum Diameter .............................. 1-13/16 In.
EIA Base ...................................... 5A
Mounting Position ............................. Any
Source ........................................ RCA RC-12 - 1934
Bulb .......................................... ST-12
Base Type ..................................... Medium 5-Pin
EIA Outline ................................... 12-5
EIA Base ...................................... 5A
Source ........................................ RCA R-10 - 1932
Heater Voltage ................................ 2.5 V
Heater Current ................................ 1.75 A
Triode
Source ........................................ RCA R-10 - 1932
Input ......................................... 3.5 pf
Output ........................................ 3.0 pf
Grid to Plate ................................. 3.3 pf
Triode
Source ........................................ RCA RC-12 - 1934
Input ......................................... 3.1 pf
Output ........................................ 2.3 pf
Grid to Plate ................................. 3.3 pf
Triode
Source ........................................ RCA RC-12 - 1934
Plate Voltage ................................. 275 V
Class A Amplifier
Source ........................................ RCA R-10 - 1932
Plate Voltage ................................. 90 V
Grid No. 1 Voltage ............................ -6 V
Amplification Factor .......................... 9
Plate Resistance (approx) ..................... 11000 Ω
Transconductance .............................. 820 µ
Plate Current ................................. 2.7 mA
Class A Amplifier
Source ........................................ RCA R-10 - 1932
Plate Voltage ................................. 135 V
Grid No. 1 Voltage ............................ -9 V
Amplification Factor .......................... 9
Plate Resistance (approx) ..................... 9000 Ω
Transconductance .............................. 1000 µ
Plate Current ................................. 4.5 mA
Class A Amplifier
Source ........................................ RCA R-10 - 1932
Plate Voltage ................................. 180 V
Grid No. 1 Voltage ............................ -13.5 V
Amplification Factor .......................... 9
Plate Resistance (approx) ..................... 9000 Ω
Transconductance .............................. 1000 µ
Plate Current ................................. 5.0 mA
Class A Amplifier
Source ........................................ RCA R-10 - 1932
Plate Voltage ................................. 250 V
Grid No. 1 Voltage ............................ -21 V
Amplification Factor .......................... 9
Plate Resistance (approx) ..................... 9250 Ω
Transconductance .............................. 975 µ
Plate Current ................................. 5.2 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
Thu, 18 Aug 2022 15:29:34 -0700