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  • Western Electric type 205D vacuum tube
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Western Electric type 205D vacuum tube

Object Details

Description (Brief)
A moderate power triode designed for use as an audio frequency amplifier, but can also be used as an RF amplifier or oscillator. Eff = 4.5 volts; Ip = 1.6 amperes. Ep = 200 - 400 volts; Ip = 8 - 40 milliamps. Mu = 6.7 - 7.4; Rp = 3500 - 4800 ohms. Tyne notes that the locking pin on 205 type tubes was set 45o differently from other tubes to prevent low-power tubes from being inadvertently substituted. Reference: Tyne, "Saga of the Vacuum Tube," page 287.
"The No. 205D is a three-element filamentary type tube intended for use as a radio-frequency amplifier, oscillator, modulator, and audio-frequency amplifier in output stages when moderate powers are required." Reference: Western Electric 205D data sheet: https://www.westernelectric.com/s/205D.pdf.
Location
Currently not on view
Credit Line
from Franklin Wingard
Data Source
National Museum of American History
date made
ca 1925
ID Number
EM.320961
catalog number
320961
accession number
241556
maker
Western Electric
Object Name
triode
vacuum tube
Measurements
overall: 4 1/4 in x 2 1/4 in; 10.795 cm x 5.715 cm
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Work and Industry: Electricity
Record ID
nmah_710265
Usage
CC0
GUID
https://n2t.net/ark:/65665/ng49ca746a5-436e-704b-e053-15f76fa0b4fa

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Open daily 10 a.m. to 5:30 p.m.

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Washington, DC 20002

Our entrance is on the corner of First Street and Massachusetts Avenue NE.

street map of Postal museum

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