Western electric 372 a brochure

Page 1

BELL SYSTEM PRACTICES SECTION AB46.372A
TRANSMISSION ENGINEERING AND DATA ISSUE I, SEPTEMBER I950
ELECTRON TUBE DATA A.T.&T. CO. STANDARD

COLD CATHODE
Western Electric

DESCRIPTION

The 372A is a three-electrode, inert-gas-filled, cold cathode tube for use in relay,
voltage regulator, or rectifier circuits. This tube is especially suitable for use in control
. circuits such as in triggering, counting, or switching apparatus.

MAXIMUM RATINGS

Peak Anode Voltage l t t 150 volts
Average Cathode Current V . . . . 10 100 milliamperes
Average Life, approximate . . . 10000 10 hours

. Transfer Current . t . . t . 5 microamperes
ELECTRON TUBE DATA SHEET
11723137 COLD CATHODE SECTION 3 72 A

COLD CATHODE

Page 2

372A - PAGE 2

MAXIMUM RATINGS, Absolute Values

Forward Peak Anode Voltage
Forward Cathode Current
Peak , .
Average ,
Averaging Time ,
Peak Inverse Anode Current
Ambient Temperature Limits

ELECTRICAL DATA

Starter Breakdown Voltage*

Starter Voltage Drop at 20 milliamperes
Anode Voltage Drop at 20 milliamperes

Transfer Current at 130 Anode Volts (D.C.)

Deionization Time, approximate
Starter Gap
Main Gap

Inverse Current at --120 Volts Anode Toteritial*l* I

MECHANICAL DATA

Mounting Position
Net Weight, approximate

Min. Bogey Max.

62
52
68

5

70
60
75

150

100

35
2

D

-55 to +85

89
74
90

volts

milliamperes
milliamperes
seconds
milliamperes
centigrade

volts
volts
volts
microamperes

, milliseconds

Any

1

milliseconds
milliamperes

ounce

* Limim apply immediately after tube has conducted current. If tube has been idle,

these values initially may be as much as 3 volts higher or lower.

** Negative anode voltage applied through 8,000 ohms. Starter connected to anode

through 100,000 ohms.

200

180

I40

120

ANODE VOLTAGE IN VOLTS

100

80

O 4 8 12

TRANSFER CURRENT IN MICROAMPERES

TRANSFER CURRENT CHARACI'ERISTIC
(TYPICAL)

16

20

24

28

32

40