Figure 7-3. Spectrum Analyzer TS-723A/U chassis, bottom view, location of parts,

TM 11-6625-255-14/TO 33A1-13-170-1

Figure 7-3. Spectrum Analyzer TS-723A/U chassis, bottom view, location of parts,

required for troubleshooting, maintenance, and

given.

repair of the spectrum analyzer, along with the

(1) Visual inspection. The purpose of visual

appropriate maintenance category, consult the

inspection is to locate faults without testing or

maintenance allocation chart, appendix B of this

measuring circuits. All meter readings or other

manual.

visual signs should be observed and an attempt

76. Organization of Troubleshooting Pro-

made to localize the fault to a particular stage.

(2) Operational tests. The operational tests

cedures

a. General. The first step in servicing a defec-

given in chapter 3 may indicate the general loca-

tive spectrum analyzer is to localize the fault,

tion of trouble and, in many instances, will help in

which means tracing the fault to a defective stage

d e t e r m i n i n g the exact nature of the fault.

or circuit. The second step is isolation, which

(3) Localization. The procedures listed in the

means locating a defective part or parts. Some

t r o u b l e s h o o t i n g table are used in localizing

defective parts, such as burned resistors and

trouble to a particular stage. The table lists

symptoms of common troubles and gives (or ref-

a r c i n g or shorted rectifiers, can be located by

sight, smell, or hearing; however, most defective

erences) corrective measures. Such a table ob-

p a r t s must be located by checking voltage and

viously cannot include all symptoms that may

resistance.

occur. The repairman should use the table as a

b. Localization and Isolation. Listed below is a

guide in analyzing symptoms that may not be

group of tests organized to reduce unnecessary

listed.

work and aid in tracing a trouble to a specific

(4) I s o l a t i o n . P r o c e d u r e s f o r i s o l a t i n g

component. Follow the procedure in the sequence

trouble are given in table 7-4.

7-4