Western electric 274 a brochure

Page 1

BELL SYSTEM PRACTICES SECTION A846.Z74A
TRANSMISSION ENGINEERING AND DATA ISSUE 1, AUGUST I948
ELECTRON TUBE DATA A.T.&T. CO. STANDARD

RECTIFIER _
FULL-WAVE, HIGH VACUUM W51?! fled!

DESCRIPTION

. The 274A is a filamentary full-wave rectifier designed to supply direct current from
an alternating current source.

CHARACTERISTICS

Filament Voltage . , . , . I 5.0 volts
Maximum Plate Voltage (RMS) pet Plate , . . 660 volts
. Maximum D-C Output Current . . . , , , 225 milliamperes

ELECTRON TUBE DATA SHEET
FILE: RECTIFIER SECTION
1-48

Page 2

274A - PAGE 2

GENERAL CHARACTERISTICS

ELECTRICAL DATA

Filament Voltage , , , , 5.0 volts
Filament Current , . . . , , _ 2.0 amperes

MECHANICAL DATA 1
Cathode , . . Coated filament

Bulb . . . , . . . . . , . . . . . . . . ST16
Base , , . , 1 . . . Medium 4- -pin
Mounting Position , Preferably vertical; if horizontal, pins

III and :4 should be 1n horizontal plane
Dimensions and pin connections shown in outline drawing on Page 4

MAXIMUM RATINGS, Design-Center Values

Peak Inverse Voltage 1500 volts
Peak Plate Current per Plate 675 milliamperes
Peak Transient Plate Current per Plate 2.5 amperes

With Choke-Input Filter:

A-C Plate Voltage per Plate (RMS) 660 volts
D-C Output Current 225 milliamperes
Minimum Input-Choke Inductance 3 henrys

With Condenser-Input Filter:

A- C Plate Voltage per Plate (RMS) 450 volts
D- C Output Current , , 160 milliamperes
Minimum Total Effective Plate-Supply Impedance per Plate 100 ohms

TYPICAL OPERATING CONDITIONS

With Choke-Input Filter:

A-C Plate Voltage per Plate (RMS) 550 volts

D-C Output Current 160 milliamperes
D-C Output Voltage, Approximate, at Input to Filter 430 volts

Filter Input Choke , 5 henrys

With Condenser-Input Filter:

A- C Plate Voltage per Plate (RMS) 450 volts

D- C Output Current 140 milliamperes
D- C Output Voltage, Approximate, at Input :0 Filter 475 volts

Total Efiective Plate- -Supply Impedance per Plate 180 ohms

Filter Input Condenser . , , 4 microfarads