Western electric 346 b brochure

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BELL SYSTEM PRACTICES ABhe . 3h613
Transmission Engineering and Data Issue 3; April 1956
Electron Tube Data A.T.&T. Co. Standard

ELECTRON TUBE DATA SHEET
WESTERN ELECTRIC 34GB ELECTRON TUBE

DESCRIPTION

The 3h6B 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 ...... . . . . . . . . 225 volts
Average Cathode Current . . . . . . . . . . . . 10 100 milliamperes
Average Life, Approximate . . . . . . . . . . . 10000 10 hours

File: Cold Cathode Section
Issue 6, April 1956

3463

Page 2

MB-w
MAXIMUM RATINGS, Absolute Values

Forward Peak Anode Voltage . . . . . . . . . . . . . 223 volts
Forward Cathode Current 1
Peak . . . . . . . . . . . . . . . . . . . . . . 100 nilliamperes
Average . . . . . . . . . . . . . . . . . . . . . 35 milliamperes
Averaging Time . . . . . . . . . . . . . . . . . 2 seconds
Inverse Peak Anode Currentl. . . . . . . . . . . . . E milliamperes
Ambient Tangerature Limits . . . . . . . . . . . . . -55 to +85 centioiade
w Min. Bagex Max.
Starter Breakdown Voltage 2. . . . . . . . . . . 55 70 89 volts
Starter Voltage Drop at 20 Milliamperes . . . . 52 60 7h volts
Anode Voltage Drop at 20 Milliamperes. . . . . . 72 80 90 volts
Transfer Current . . . . . . . . . . . . . . . . See curve - Fig. 3
Ionization Time - Starter Gap 3. . . . . . . . . --- 6 --- milliseconds
Deionization Time, Approximate
Starter Gap . . . . . . . . . . . . . . . . . --- 2 --- milliseconds
Main Gap . . . . . . . . . . . . . . . . . . --- 8 --- milliseconds
Inverse Current at _
-120 Volts Anode Potential L. . . . . . . . . - --- 3 millimnperes

MECHAHICAL DATA

Mounting Position . . . . . . . . . . . . . . . . . . . . . . . . Any

Net Weight, Approxizate . . . . . . . . . . . . . . . . . . . . . 1 ounce

Dimensions and pin connections shown in outline drawing on page h

Note 1: Sufficient resiStance must be used in series with the tube to
assure that the electrode currents do not exceed their maximum
rated values.

Note 2: Limits apply immediately after tube has conducted current. If the
tube has been idle, these values initially any be as much as 3
volts higher or lower.

Note 3: with 15 volts starter overvoltage (15 volts above Starter Breakdown
Voltage) with tube in total darkness.

Note h: Negative anode voltage applied through 8000 ohms. Starter connected
to anode through 100000 ohms.
HA3

western Electric cold Cathode tubes contain a minute amount of radium bronide
which is a radioactive material. The amount in most types is too small to require
any special care in use, handling or disposal.

A few types contain a larger quantity of radium bromide in which the radium
approximates that found on a luminous watch dial. These types bear a red three-
bladed propeller-shaped s1_hol on the tube envelope. Instructions for handling
such tubes are given below and also in Bell System Practices for Central Office
maintenance.

Installations ordinarily require no precautions against radiation. However,
quantities of the tubes should not be so installed, or so stored outside the
shipping carton, that they will be within a few inches of personnel or in proxi-
mity to photographic film for extended periods of tine. For example, however, a
hO-hour week exposure at about one (1) foot from a bank of 500 tubes (covering
an area of 20 inches x #5 inches) is well within the accepted tolerance limits
for personnel. Reasonable care should be exercised in handling and disposal of
broken tubes. In general, attention should be given to the following:

(3) Avoid breathing dust or vapors from broken tubes.

(b) Avoid contacting broken parts with bare hands.

(0) Use wet rag to pick up broken parts. Wrap broken parts in rag and tie
securely so as to form a package. Thoroughly wash hands after disposal.

(d) Dispose of broken or defective tubes as they are taken out of service.
One or two tubes at a time nay be disposed of with normal waste material.
Accumulation of tubes in one concentrated area of the place of final
diSPOSlbiOD should be avoided.