TM 55-1930-209-14&P-12
Table 4-3. Telephone System Troubleshooting (continued)
Condition
Possible Cause
Suggested Action
7. Strobe light not
a. Bulb burned out
a. Replace bulb; see para 4-18
operating
2.8.2
b. Circuit breaker 10P13
b. Close (ON) circuit breaker
or 10P13A-7 supplying
120 Vac open (OFF)
c. See 2b and c above
c. See 2 b and c above
d. Strobe light
d. Test and if necessary replace
malfunctioning
strobe light; see para 4-18.2.8.3
8. Station buzzer does
a. Circuit breaker 10P13
a. Close (ON) circuit breaker
not sound
or 10P13A-7 supplying
120 Vac open (OFF)
b. See 2b and c above
b. See 2b and c above
c. Buzzer malfunctioning
c. Test and if necessary replace
buzzer; see para 4-18.2.9
4-18 Maintenance procedures
WARNING
To prevent electrical shock, open circuit breakers 10P13A-7 on emergency light panel and 3P14 on 24 Vdc
power panel. Redtag circuit breakers with "WARNING - DO NOT ACTIVATE - REPAIRS BEING MADE."
NOTE
Due to the mission and crew capabilities, maintenance normally assigned to higher echelon of maintenance
may be assigned to the crew.
4-18.1 General maintenance. Perform appropriate general maintenance procedures in paragraph 2-18. Clean and
inspect electrical components as follows:
a. Wipe clean exterior of electrical component with clean rag Vacuum clean or clean Inside with electrician's brush.
Avoid using solvents for cleaning inside of component. Solvents leave a greasy film on components that may reduce
electrical continuity.
b. Visually inspect for indications of burns, corrosion, loose connections, damaged parts, or chipped paint. Clean
corrosion from contacts and terminals, tighten loose connections, and replace damaged parts. Clean electrical
contacts with silver polish, fine sandpaper, or burnishing tool DO NOT use emery paper or steel wool. Vacuum to
remove residue. Touch up paint according to TB 43-0144. Do not paint threads or labels.
4-18.2 Equipment maintenance
4-18.2.1 Handset station (desk telephone)
4-18.2.1.1 Test and repair. Operationally test handset If handset is not properly sending or receiving signals, do not
repair handset. Replace handset station as given in paragraph 4-18.2.1.2.
4-16
