NJ7P SQL Tube Database Query

A horizontal ribbon.

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A horizontal ribbon.

12BR7A
Twin Diode - High-Mu Triode

EIA Base & Outline

EIA Base: 9CFEIA Bulb: 6-2
Source ........................................ ARRL HB - 1964

Application

Source ........................................ ARRL HB - 1964
Miniature type used in tv applications. Requires miniature 9-contact socket.

Mechanical Data

Source ........................................ ARRL HB - 1964
EIA Outline ................................... 6-2
EIA Base ...................................... 9CF

Electrical Data

Source ........................................ ARRL HB - 1964
Heater Voltage ................................ 6.3/12.6 V
Heater Current ................................ 0.45/0.225 A

Direct Interelectrode Capacitances (approx)

Diode
Source ........................................ ARRL HB - 1964
Output ........................................ 2.0 pf
Grid to Plate ................................. 0 pf

Triode
Source ........................................ ARRL HB - 1964
Input ......................................... 2.8 pf
Output ........................................ 1 pf
Grid to Plate ................................. 1.9 pf

Characteristics and Typical Operation

Class A Amplifier
Source ........................................ ARRL HB - 1964
Plate Voltage ................................. 100 V
Grid No. 1 Voltage Derived from
Cathode Bias Resistor ...................... 270 Ω
Amplification Factor .......................... 60
Plate Resistance (approx) ..................... 15K Ω
Transconductance .............................. 4000 µMho
Plate Current ................................. 3.7 mA

Class A Amplifier
Source ........................................ ARRL HB - 1964
Plate Voltage ................................. 250 V
Grid No. 1 Voltage Derived from
Cathode Bias Resistor ...................... 200 Ω
Amplification Factor .......................... 60
Plate Resistance (approx) ..................... 10.9K Ω
Transconductance .............................. 5500 µMho
Plate Current ................................. 10 mA

A horizontal ribbon.

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A horizontal ribbon.

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Fri, 24 Jun 2022 17:46:42 -0700