Figure 7-4. Spectrum Analyzer TS-723B/U chassis, bottom view, location of parts.

TM 11-662525514/TO 33A1131701

Figure 7-4. Spectrum Analyzer TS-723B/U chassis, bottom view, location of parts.

78. Localizing Trouble

(5) Techniques. Applicable techniques are

a. General. Procedures for localizing trouble

( 6 ) Intermittent troubles. In all the tests,

are given in table 7-4 below. Parts locations are

the possibility of intermittent trouble should not

i n d i c a t e d i n f i g u r e s 7 - 1 , through 7 - 5 . A

be overlooked. This type of trouble, if present,

schematic diagram of B + voltage distribution is

m a y often be made to appear by tapping or

shown in figure 7-6. Voltage and resistance meas-

j a r r i n g the equipment.

urements are shown in figures 7-7 and 7-8.

D e p e n d i n g upon the nature of the operational

7-7. Troubleshooting Setup

symptoms, one or more of the localizing proce-

The spectrum analyzer must be connected to a

dures will be necessary. When trouble has been

115- or 230-volt ac source and to test equipments

l o c a l i z e d to a particular stage, use voltage and

which vary from test to test. Remove the top and

r e s i s t a n c e measurements to isolate the trouble.

b o t t o m dust covers and connect the audiofre-

quency oscillator and oscilloscope as specified for

CAUTION

t h e particular tests given in table 7-4.

If operational symptoms are not known,

7-5