Adjusting Motor Speed (Not Applicable on TT-335/TG and TT-537/G)

TM 11-5815-206-12/ TO 31W4-2PGC1-61

Figure 2-5. Teletypewrirer TT-4(*)/TG or TT-698(*)/TG

d . Hold the vibrating end of the tuning fork

(a) S c o o p o u t a h o l e a b o u t 6 i n c h e s i n

diameter and about 6 inches deep.

close to one eye and look through the slots in the

vibrating shutter to view one of the white dots on

(b) Drive a rod vertically into the hole until

the top of the rod is approximately 3 inches below

the governor target (fig. 1-9).

e . Make no adjustment if the selected spot

the surface of the earth. Swing the driving hammer

carefully to avoid whipping of rod (whipping

appears to be motionless. If the spot appears to be

results in poor contact between the rod and the

moving clockwise, pull the end of the governor

soil).

adjustment worm outward. Release the worm when

t h e apparent clockwise motion of the spot has

stopped. If the spot appears to be moving

ground rod. Be sure to obtain a good bond be-

counterclockwise, push the end of the governor

tween the rod and the lead. Connect the other

adjustment worm i n w a r d u n t i l t h e a p p a r e n t

end of the lead to the pigtail on the plug of the

counterclockwise motion of the spot has stopped.

motor power cord.

To avoid overadjustment, release the worm just

(d) Saturate the earth around the top of

before the spot appears to come to a halt.

the rod with water, fill the hole around the rod

with earth, and add more water.

f. Replace the tuning fork in its storage clips on

the rear of the front door. Be sure to insert the

(e) If the soil in the area normally is not

fork between the clips and the springs. Do not

moist, drive another ground rod approximately 15

feet from the first rod and connect it to the first

insert the fork between the springs and the door.

NOTE

rod. If the soil is exceptionally dry, drive several

additional rods to form two rows of rods with a

The motor speed adjustment procedure is

minimum of ten feet between the rows and connect

the same for all operating speeds of the

the rows in parallel. Add water occasionally (daily,

teletypewriter, as described in paragraph 1-

if necessary) to maintain good contact between the

4c. If the teletypewriter is to be operated

ground rods and the soil.

a t a speed other than 60 wpm, the ap-

p r o p r i a t e worm and worm gear must be

2-8. Adjusting Motor Speed (Not Applicable on

i n s t a l l e d . This procedure is b e y o n d t h e

TT-335/TG and TT-537/G)

scope of the operator's duties and must be

a. Remove the tuning fork from the clips on the

performed by higher category maintenance

rear of the front door on the dust cover.

personnel.

b. Turn the MOTOR switch to ON (fig. 1-8).

Allow the motor to run for several minutes.

c . Strike the tuning fork g e n t l y a g a i n s t t h e

hand to set it into vibration.

2-6