Summary
The pentode section of this valve which had a semi-remote cut-off characteristic was primarily intended for use in radio receivers as an intermediate frequency (I.F.) amplifier, the diode sections were used as signal detector and automatic volume control (A.V.C.) rectifier. The pentode section was also frequently used as the first audio stage. 2.5 volt indirectly heated cathode.
Physical Description
Shouldered glass bulb with top cap and American style small 7 pin base mounted on display block.
More Information
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Collecting Areas
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Manufacturer
Hygrade - Sylvania Corporation., United States of America, 1933
Note; the date code (J3) indicates 1933 (May) manufacture. -
Inscriptions
Bulb: 2B7 Base: Hygrade/J/3 Display block: DUO-DIODE-PENTODE 2B7/ Hygrade Made in U.S.A./Heater Cathode; 2.5 volt, 0.8 amp./Used as second detector in Superhet./Receivers about 1936-37/Base:- Standard 7-Pin/Pres. by J.C.Liddy
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Classification
Electronics, Vacuum technology, Amplification & rectification
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Category
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Discipline
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Type of item
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Overall Dimensions
110 mm (Length), 38 mm (Outside Diameter)
Display block not included.
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Keywords