AN/PRR-9(XE-9) Limiting Test

TM 11-5820-549-50-1

Kz external modulation from the TS-421A/U. The

f. Adjust the AN/URM-48 output successively to

AN/URM-103 output should be zero at this point.

10,000, 1,000, 500, 100, 10, and 1.0 microvolt levels,

e. Set the receiver volume control for maximum,

noting the change from the 3.5 milliwatt (mw) reference

level as indicated on the TS-585A/U at each of these

squelched operation. Remove plug from headset jack

steps. Output level shall not vary more than 1.75 mw

and listen to horn transducer to be sure receiver is

at any of the settings of the AN/URM-103.

squelched. Then replace plug in headset jack.

f. Increase the AN/URM-103 output until current

4-9.

AN/PRR-9(XE-9) Audio Frequency Response

on TS-352B/U increases approximately 10 to 12

Test

milliamperes.

a. Connect the test equipment as shown in figure

g. Note and record indication of AN/URM103 RF

4-4.

ATTENUATOR MICROVOLTS dial.

b. Set the PP-3514/U for 3.2 0.1 volts input to the

h. AN/URM-103 output shall not exceed 0.4

receiver.

microvolts.

c. Set the TS-585A/U for 150 ohms.

4-8. AN/PRR-9(XE-9) Limiting Test

d. Set the AN/URM-48 to the receiver channel

With the exception of the TS-723A/U, this test uses the

frequency at 5,000 microvolts output level.

same test setup as figure 4-2. The receiver is operated

e. Set the TS-421A/U for 1,000 cps and adjust

on any normal channel frequency.

output for an indication on the AN/URM48 of 8.0 kc

a. Connect the test equipment, with the exception

deviation.

cited, as shown in figure 4-2.

f. Set the receiver volume control to squelch "off"

b. Set the PP-3514/U for 3.2 0.1 volts input to the

and adjust for a 3.5 milliwatt indication on the TS-

receiver.

585A/U.

c. Set the TS-585A/U for 150 ohms.

g. Note the db indication on the ME-30A/U. This is

d. Set the AN/URM-103 to receiver channel

the reference level for subsequent measurements.

frequency and 8.0 kc deviation at 1,000 cps. Set the

h. Change the TS-421A/U modulating frequence

generator output at 100,000 microvolts.

successively, to the frequencies indicated below.

e. Adjust the receiver volume control for 8.5

Output changes as indicated on the ME30A/U shall be

milliwatts output as indicated on the TS-585A/U. This

within the range shown in the "Response" column below.

output is the reference level.

Figure 4-3. AN/PRR-9 (XE-9) squelch sensitivity test.

4-3