Section III. PRELIMINARY OPERATING PROCEDURES

13. Operating Precautions

(fig. 3)

a. Do not insert a tube into a test socket until the SELECTORS

switches and the FILAMENT RANGE switch are properly ad-

justed (par. 16).

b. R e t u r n a l l c o n t r o l s t o t h e i r s a f e t y p o s i t i o n s ( p a r . 1 5 d ) w h e n

the tube tester is turned off.

c. Do not prolong the testing of tubes with filaments that draw

more than 3 amperes.

d. I n s p e c t t h e b a s e s o f s e v e n - a n d n i n e - p i n m i n i a t u r e t u b e s f o r

bent pins before inserting the tube into the test socket. If any

pins are bent, straighten and aline them by inserting the tube

into the proper pin straightener (mounted on the inside of the

cover of the tube tester (fig. 1)) and pressing the tube down

firmly.

14. Tube Test Sockets and Test Adapters

After the controls on the tube tester have been set as directed

in the tube test data roll chart (par. 12), place the tube to be

tested in the proper tube test socket listed below.

a. Tube Test Sockets (fig. 3).

Tube type tested

Tube test socket

Four-pin standard tubes.

FOUR -----------------------------------------

Five-pin standard tubes.

FIVE -----------------------------------------

Loctal base tubes.

LOCTAL -------------------------------------

Six-pin standard tubes.

SIX --------------------------------------------

Seven-pin miniature tubes.

MIN. SEVEN ----------------------------------

Eight-pin, long-lead subminiature tubes.

SUB-MIN. EIGHT LONG LEAD_

Seven-pin transmitting tubes.

TRANSMITTING SEVEN PIN----------

Nine-pin miniature tubes.

NOVAL --------------------------------------

Octal base tubes.

OCTAL ----------------------------

Seven-pin standard tubes.

SEVEN ------------------------------------------

Acorn tubes.

ACORN ------------------------------------

Seven-pin subminiature tubes.

SUB-MIN. SEVEN ----------------------------

Eight-pin subminiature tubes.

SUB-MIN. EIGHT ----------------------------

b. Test Adapters. A test adapter X13B (fig. 1) is included to

p r o v i d e a test socket for eight-pin, subminiature, long lead tubes.

Three test adapters (fig. 5) (X3B (eight-pin octal), X7B (nine-

pin noval), and X1OB (seven-pin miniature)) are included with

each TV-2B/U. The test adapters are installed in their corre-