Carrier error

Test procedure

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

(2)On the UUT set:

Carr Freq

1200 MHz

RF Level

0 dBm

(3)On the modulation meter select CARRIER ERROR. The FREQUENCY display will read 0.00 kHz.

(4)On the UUT set:

Mod Mode

FM External

FM1 Level

100 kHz

Source On

 

Mod On

 

DC coupling

 

Null DCFM

 

(5)On the modulation meter measure the carrier frequency error displayed in the FREQUENCY window checking that the result is within the specification shown in Table 5-24.

External FM frequency response (ALC off, DC coupled)

Test procedure

 

UUT

2305

 

Modulation meter

Function generator

 

RF

 

OUT

 

EXT MOD

RF

OUTPUT

INPUT

INPUT

 

 

LF

Temporary

 

OUTPUT

connection

50

 

DVM

load

 

 

Audio analyzer

 

 

 

 

INPUT

 

 

C2565

Fig. 5-8 External modulation and modulation distortion test set-up

30 Hz to 100 kHz

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

(2)On the UUT set:

Carr Freq

15 MHz

RF Level

0 dBm

Mod Mode

FM External

FM1 Level

50 kHz

Source On

 

Mod On

 

DC coupling

 

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

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

5-12

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VXI 3002 manual Carrier error, External FM frequency response ALC off, DC coupled, Hz to 100 kHz