Section V
Paragraphs 5-12 to 5-21
5-17. LUBRICATION.
5-18. The signal generator must be lubricated at
5-13. REPLACEMENT OF TUBES.
least every 500 hours as follows:
5-14. All tubes in the signal generator are of the
a. Remove the signal generator from its case.
miniature type and are shielded. Remove the shield
by pushing it down and rotating it 1/4 turn counter-
b. Remove the top and bottom covers from the r-f
clockwise. Remove tube by pulling it straight out of
chassis.
its socket, taking care not not bend the base pins.
Thoroughly test a suspected tube before discarding.
c. Apply AN-G-25 grease as follows:
If replacement does not correct operation, always re-
insert the original tube. To gain access to tubes in
LOCATION
AMOUNT
PART
the signal generator, proceed as follows. See figure
5-3 for tube location.
Dynamotor
Each end of unit. Small amount. See
a. Loosen four fillister head captive screws on each
section VI, para-
side of the signal generator front panel.
graph 6-36.
10, figure 6-10.
Small amount on
b. Grasp the two panel handles and remove the sig-
Attenuator
nal generator from its case. The tubes in the audio
spur gear.
gear teeth.
and univerter chassis are now accessible.
Attenuator
5, figure 6-10.
Small amount on
c. To gain access to all the tubes in the r-f chassis,
top and sides.
plunger
except V1501 and V1502, remove the top cover of the
drive rack.
r-f chassis.
d. Apply AN-0-4 oil as follows.
d. To gain access to V1502, remove the r-f chassis
rear cover.
NOTE
e. To gain access to V1501, remove the r-f chassis
AN-0-6A oil may be used as an alternate.
bottom cover.
LOCATION
AMOUNT
PART
One drop if binding
CARRIER
8, figure 6-5.
Do not remove tubes with power applied to the
or squeaking
SET control
equipment. H e a t e r s a r e w i r e d t n v a r i o u s
occurs.
shaft bushing.
series-parallel combinations and removal of
one tube may overload and burn out other
MICROVOLTS 7, figure 6-5.
One drop if binding
heaters. See figures 4-29 and 4-30 for fila-
control shaft
or squeaking
ment circuits.
occurs.
bushing.
NOTE
One drop.
R-f slug rack
8, 9, figure
oil retaining
In the event that tubes are changed, check the
felt washers.
associated circuit functioning for proper align-
11, 12, fig-
One drop if binding
ment. Univerter tube changes may consider-
Attenuator
ably affect univerter alignment due to the high
ure 6-10.
or squeaking
spur gear.
occurs.
frequencies involved. See Section VI, para-
graph 6-42 for alignment instructions.
e. Replace r-f chassis covers and secure the signal
5-15. REPLACEMENT OF FUSES.
generator in its case.
5-16. The power input line to the signal generator is
protected by two fuses mounted on the front panel. To
remove, turn cap 1/4 turn counterclockwise to unlock
operational check given in paragraph 5-3 and the ac-
and pull fuse from holder. If a replaced fuse blows
immediately, investigate the circuits for an overload
curacy checks given in paragraphs 5-4 through 5-8,
or short circuit before further replacement.
should be performed periodically for periods not ex-
ceeding 100 hours.
Never replace a fuse with one of higher rating
spection periodically for periods not exceeding 500
unless continued operation is of such impor-
hours.
tance as to warrant possible damage to the
equipment.
a. Remove the signal generator from its case.
