TM 9-4910-644-14 & P
b. Crank or rotate magneto breaker cam slowly.
c. When both sets of points of the magneto are open, both indicator lamps will glow. When one set of points
closes, the one corresponding lamp goes out.
d. While rotating the magneto slowly, if both lamps glow at the same time and conversely if both go out at the
same time, the magneto points being checked are properly synchronized.
e. IMPROPER TIMING of the points is indicated when the two lamps do not glow at the same time while the
magneto cam is being rotated. An adjustment must be made on the points to bring the lamps into synchroniz-
ation.
a p p l i c a b l e TM for correct breaker point adjustment procedures. With
Refer to the
instrument hooked up, proceed with point adjustment until proper synchronization is accomplished.
1-8. TO CONSERVE BATTERIES.
Always switch OFF and close cover when not in use.
1-9. MAINTENANCE INSTRUCTIONS.
Replace batteries if the neon lamps do not glow brightly or do not light. There are no periodic maintenance
requirements.
1-10. BATTERY REPLACEMENT.
a. Remove the two knurled screws at the back of unit. Remove panel by sliding it forward toward the lead
storage and lifting it out.
b. Replace the three D cells in the battery holder, the red polarity caps provide the proper polarization.
Replace the panel and the two hand screws.
1-11. LAMP REPLACEMENT.
Remove lamps by unscrewing from the front of the panel. Replace with neon lamps type NE45 only.
1-12. OSCILLATOR TRANSFORMERS.
The oscillator transformers are mounted to the front panel and may be replaced as a set of two. Remove the
front panel and the transformer mounting screws, refer to the circuit schematic for the wire color coding.
1-13. LUBRICATION.
There are no lubrication requirements for this unit.
1-14. CALIBRATION.
There are no calibration requirements for this unit.
1-15. TROUBLESHOOTING.
The following is a table of the troubles which may be encountered, their probable causes and remedies.
REMEDY
TROUBLE
PROBABLE CAUSE
Replace
batteries.
Neon lamps do not glow.
Defective
battery
Defective
neon lamps
Replace
lamps.
Replace
oscillator transformers.
Defective
oscillator
Defective
switch
Replace
switch.
Neon lamps glow but do not
Defective red or black test leads
Repair or replace test leads.
go out when black and red
Defective oscillator
Replace oscillator transformers.
leads are connected to-
gether.
1-16. ADDITIONAL DATA.
Additional copies of this publication may be obtained through normal DA distribution channel from the following
a d d r e s s : Commander, U.S. Army Publication Center, 1655 Woodson Rd. St. Louis, MO. 63114.
Reproduction for non-military use of the information or illustrations contained in this publication is not per-
mitted. The policy for military use reproduction is established for the Army in AR 380-5, for the Navy and
Marine Corps in OPNAVINST 5510.1B, and for the Air Force in AFR 205-1.
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