(8)Set the UUT to RF level +19 dBm and repeat (2) to (5) using Table 5-33.

AM scale shape

Test procedure

(1)Connect the test equipment as shown in Fig. 5-7.

(2)On the UUT set:

Carr Freq

100 MHz

RF Level

0 dBm

Mod Mode

AM Internal

Source On

 

Mod On

 

AM1 Level

30%

(3)On the modulation meter, select CAL, AM, 300 Hz ￿ 3.4 kHz LF filter.

(4)Measure the AM accuracy at the depths shown in Table 5-34 checking that the results are within specification.

External AM frequency response (ALC off, DC coupled)

Test procedure

100 Hz to 30 kHz

(1)Connect the test equipment as shown in Fig. 5-8.

(2)On the UUT set:

Carr Freq

400 MHz

RF Level

−4 dBm

Mod Mode

AM External

AM1 Level

80%

Source On

 

Mod On

 

DC coupling

 

(3)Set the function generator to give 1 V RMS, 1 kHz sine wave.

(4)On the modulation meter select CAL, AM, 10 Hz ￿ 300 kHz filter.

(5)On the modulation meter check that the AM reading is between 76% and 84%, then set a reference using the relative function.

(6)Record the absolute reading for use in the formula in (16) below.

(7)Set the function generator to each of the frequencies shown in Table 5-35 checking that the relative readings on the modulation meter are within specification.

(8)Set the UUT RF level to +7 dBm and repeat (3) to (7) using Table 5-36.

(9)Set the UUT RF level to +13 dBm and repeat (3) to (7) using Table 5-37.

5-16

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VXI 3002 manual AM scale shape, External AM frequency response ALC off, DC coupled, Test procedure Hz to 30 kHz