ASSEMBLY AND PREPARATION FOR USE.

ARMY

TM 9-6650-235-13&P

MARINE CORPS

TM-08552A-13&P

2-6. ASSEMBLY AND PREPARATION FOR USE.

NOTE

The objective tube assembly (1)

consists of two sections. It contains

the objective lens optical cell

assembly (2) and is connected to the

illuminating head assembly (3)

whether or not any borescope

extension tubes (4) are used.

Borescope extension tubes (4)

consist of two sections each. Use of

only one section or odd number of

sections will present a blurred,

unfocused image.

a. Open the borescope optical case (5) and remove

the objective tube assembly (1) and the correct number

of borescope extension tubes (4). (Refer to table 2-2,

page 2-16 for the number of borescope extension tubes

required for each cannon bore.)

WARNING

careful

when

engaging/

disengaging the two pieces of the

objective

tube

assembly

borescope extension tubes to avoid

pinching the thumb.

b. Connect the two pieces (1) of the objective tube

assembly together by first alining the key (6) with the

corresponding keyway (7) in the other piece and then

engaging the two pieces so the lines (8) marked OBJ are

alined.

2-12