Section VII. RADIO INTERFERENCE SUPPRESSION
a. Interference. The term "interference" as used
herein applies to electrical disturbances in the radio
frequency range which are generated by the conversion
and storage unit and which may interfere with the proper
operation of radio receivers or other electronic
equipment, or enable the enemy to locate the
b. Interference Suppression. The term "interference
suppression" as used herein applies to the methods
used to eliminate or effectively reduce radio interference
generated by the conversion and storage unit.
4-19. General Methods Used To Attain Proper
Essentially, suppression is attained by providing a.
methods used to attain suppression include shielding the
ignition and high-frequency wires, grounding the frame
with bonding straps, and using capacitor and resistors
4-20. Interference Suppression Components
a. Gasoline Engine Spark Plugs and Ignition Cables.
The gasoline engine is equipped with shielded spark
plugs (1, fig. 4-23 1) and shielded ignition cables (3).
Braided metal covering woven around the insulation on
high tension leads are grounded through the magneto to
provide a low resistance path for grounding interference
generated in the circuit.
Shielded spart plug
8. IE toothed lockwasher
Shielded ignition cable
Do not pull on cable or twist braided
shielding. Gently work cable from
11. Timing gear cover
side to side and free the rubber seal.
12. Cylinder block
Do not use sharp tools to install
13. Cylinder head
Figure 4-28. Ignition suppression components (sheet 1
completely inclosed by a metal housing which is
grounded by the mounting. Electrical contact between
the mounting surfaces is accomplished by the use of
internal-external tooth lockwashers (8).
the ignition unit.
e. Conversion Heater. The conversion heater base
ignition cables (3) carry current from the magneto (6) to
the shielded spark plugs (1).
(8) is grounded by the mounting to the housing.
c. Heater Spark Plug and Igniter Cable. The
Electrical contact between mounting surfaces is
conversion heater is equipped with a shielded spark plug
accomplished by the use of internal-external tooth
(6, fig. 4-23 2) and igniter cable (3). Braided metal
suppressed by suppressors (14) on the motor.
d. Ignition Unit. The ignition unit (13) is inclosed by
4-21. Replacement Of Suppression Components
a metal housing, grounded to the mounting. Internal-
Refer to figure 4-23 and replace suppression
between the mounting surfaces. Suppressor