Section III. TROUBLESHOOTING

TM 11-5826-258-24

Table 3-2. Bench Test Preventive Maintenance-Continued

Total taskhours required: 3.74

Work

Sequence

ITEM TO BE INSPECTED

Time

No.

PROCEDURE

(T/H)

a. Rf sensitivity test.

b. Course centering test.

c. Deflection sensitivity test.

d. Age response test.

e. Warning signal teat.

MARKER BEACON RECEIVER SECTION

Perform the following tests in accordance with paragraph 3-22.

a. Audio output power teat.

b. Lamp actuation teat.

c. Threshold sensitivity test.

Section III. TROUBLESHOOTING

3 - 6 . General

3-7. Corrective Action

Troubleshooting the receiver and receiver control is

Corrective action is limited to removal and replace-

limited to functional checkout on the flight line, com-

ment of the components described in section IV.

ponent substitution indicated in table 3-3, and veri-

Troubleshooting or repair beyond that described in

fication by bench testing.

this manual is not authorized. If the receiver or control

fails any one of the bench tests, all testing will stop

and the unit must be returned to the manufacturer.

Table 3-3. Troubleshooting

Probable cause

Corrective action

Malfunction

Replace faulty bulb(s) (para 3- 13)

Panel lamp(a) do not light

Faulty bulb(s)

Check by substitution (para 3-10 and

Faulty receiver, control, or other units not

System does not function as specified in

3-12). Refer to the appropriate manuals

the flight line tests (ch 3, sec V)

part of this receiving set

for substitution of interfacing equipment

not part of this receiving set.

Refer defective receiver or control unit to

higher category of maintenance for

bench test (ch 3, sec VI)

Faulty receiver and/or control unit.

System does not function as specified in

Return to manufacturer for repair under

warranty.

the bench tests (ch 3, sec VI)

Section IV. MAINTENANCE

tide thorough ventilation whenever used. DO

3 - 8 . General

NOT USE NEAR AN OPEN FLAME. Tri-

Maintenance of the radio receiver set is limited to the

chloroethane is not flammable, but exposure

procedures in this section and the following sections in

of the fumes to an open flame or hot metal

this chapter. Personnel are cautioned that the manu-

surface forms highly toxic phosgene gas.

facturer's warranty is voided if the receiver is opened

b. Remove grease, fungus, and ground-in dirt from

by military personnel or if repair beyond that covered

the equipment cases and mounting, Use a cloth

in this manual is attempted. Components found de-

dampened (not wet) with trichloroethane.

fective in the bench tests in section VI or section VII

c. Remove dust or dirt from cable and equipment

are to be returned to the manufacturer.

connectors with a soft brush. Remove grease or grime

with a lint-free cloth moistened with trichloroethane.

3-9. Cleaning

Dry with compressed air.

Inspect the exteriors of the control unit, receiver, and

d. Clean the control unit front panel and the control

mounting. The exterior surfaces and vibration iso-

knobs with a soft clean lint-free cloth. If dirt is hard to

lators on the mounting should be free of dust, dirt,

remove, dampen cloth with water or for more effective

grease, and fungus,

cleaning, use a mild soap.

a. Remove dust and loose dirt with a clean, soft

cloth.

3-10. Removal and Replacement of Re-

WARNING

ceiver

The fumes of trichloroethane are toxic. Pro-

a. Removal.

3-3