SECTION 4. INTERMEDIATE TESTING PROCEDURES USING RADAR TEST SET AN/TPM-25A

TM 11-4920-296-14&P

SECTION 4

INTERMEDIATE TESTING PROCEDURES USING RADAR TEST SET AN/TPM-25A

4-1. GENERAL

abnormal indications are observed for the receiver sensitiv-

ity check (2), or for the transmitter power check (5),

4-2. This section contains the intermediate testing pro-

refer to table 4-4 and make the appropriate adjustments.

cedures and instructions for Transponder Set Test Set

If the adjustment procedure cannot be correctly performed

AN/AW-378. Information is included to check out the

or if other indications are incorrect, proceed to Section 3,

main functions of the test set.

paragraph 3-9 Troubleshooting, to isolate that faulty

module.

4-3. TEST EQUIPMENT REQUIRED

4-8. Mode 4 testing procedures of the test set will be

4-4. Table 4-1 lists the test equipment required for inter

performed at the end of the table 4-3 in the checkout

mediate testing procedures of the test set.

procedures numbered 8-11. and 4-4 give the corresponding

4-5. INTERMEDIATE CHECKOUT

test setups. These Mode 4 checks are: (8) Pretrigger; (9)

PROCEDURES

Interrogation video; (10) SLS pulse; and (11) GTC signal.

Figure 4-5 provides the fabrication and wiring details for

4-6. Table 4-2 lists the AN/TPM-25A standard switch

the Mode 4 connector.

settings for tests conducted on the AN/APM-378. Individual

tests will indicate change from this listed standard.

4-9. If all are correct (as indicated in table 4-3), and the

AN/APM-378 responds correctly to all of the input signals

4-7. Table 4-3 lists the test and procedures required for

designated, the AN/APM-378 test set is proven to be fully

confirming that the test set is operating correctly. Figures

operational.

and 4-2 provide various test setups used in conjunction

with the procedures of table 4-3. These checks should be

4-10. The preliminary Tests and Preliminary Setup given

perfomed after repair actions. The intermediate checkout

in table 4-3 allow adequate warm-up time for the test set;

is divided infections which check for: (1) Power supply

make preliminary lamp tests and control settings prior

voltages; (2) Receiver sensitivity; (3) Receiver frequency

to actually preforming operational checkout. After the pre-

and bandwidth; (4) Receiver reference code, emergency

liminary procedures/tests have been performed the inter-

and I/P function, (5) Transmitter power; (6) Transmitter

mediate checkout procedures may be performed.

frequency; and (7) Transmitter plus characteristics. If

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