Section VI. RADIO INTERFERENCE SUPPRESSION

TM 5-4110-217-14

Section VI. RADIO INTERFERENCE SUPPRESSION

3-16.

Definition.

a. Interference. The term "interference" as used

herein, applies to electrical disturbances in the radio

frequency range which are generated by the refrigeration

unit and which may interfere with the proper operation of

radio receivers or other electronic equipment

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 refrigeration unit.

3-17.

General Methods used to Attain Proper

Suppression.

Essentially, suppression is attained by providing a

low resistance path to ground for the stray currents. The

methods used include shielding the ignition and high-

frequency wires, grounding the frame with bonding

straps, and using capacitors and resistors.

3-18.

Interference Suppression Components.

a. Primary Suppression Components.

The

primary suppression components are those whose

primary function is to suppress radio interference.

b. Secondary Suppression Components. These

components have radio interference suppression

functions which are incidental and/or secondary to their

primary function.

3-19.

Replacement of Suppression Components.

(Model RMP-J/1-1OG)

a. Removal (figure 3-8).

(1) Unscrew both ignition cables at the spark

Figure 3-8. Radio Suppression Components (Model

plug and ignition coil. Remove cable from unit.

RMP-J/1-10G)

(2) Unscrew spark plug from engine cylinder

burned points, cracks, or damaged threads. Inspect

head. Remove spark plug and washer

capacitor for damage or breaks. Replace all defective

(3) Disconnect wiring at capacitor

parts

(4) Unscrew nut, washer and screw that

c. Installation.

To install radio suppression

secure capacitor to bracket. Remove capacitor.

components, reverse removal procedure (paragraph 3-

NOTE

19a).

Do not pull on the ignition cable or twist

the braided shield Gently work the cable

3-20.

Testing of Radio Interference Suppression

from side to side and free the rubber

Components.

seal Do not use sharp metal tools to

Test the capacitor for leaks and shorts on a

Install the rubber seals.

capacitor tester, replace defective capacitors. If test

equipment is not available and interference is indicated,

Cleaning and Inspection

isolate the cause of the interference by the trial and error

(1) Clean parts in an approved cleaning

method of replacing the capacitor, spark plug, or ignition

solvent and dry thoroughly.

cable with known good parts In turn until the cause of

(2) Inspect cable for frayed insulation, loose

Interference is located and eliminated.

connectors, or other damage. Inspect spark plug for

Change 3 3-11