Internal AM Frequency Response

AM frequency response describes the variation of the actual AM modulation depth vs. modulation rate at a given CW frequency. In this test, the AM rate is varied from DC to 10 kHz and the DUT CW frequency is varied from 501 kHz to 2.0 GHz.

AM depth is set to 30% or 60% at a reference AM rate of 1 kHz. The actual depth is measured with a measuring receiver and stored as the reference depth. While the depth setting on the ESG remains constant, the actual depth is measured for AM rates between DC and 10 kHz.

 

Instrument

Critical Specifications for This Test

Recommended Model

Measuring Receiver

AM Depth Accuracy

8902A

Mixer

Not used for ESGs with frequency range <2 GHz

RF/LO Freq. Range:   1 to 2800 MHz

IF Frequency Range: 1.5 MHz

RF 1 dB compression:   +8 dBm

RF/LO Freq. Range:   500 to 9000 MHz

IF Frequency Range: 50 MHz

M/A-COM MDC-174

M/A-COM MDC-164

Local Oscillator

Not used for ESGs with frequency range <2 GHz

Frequency Range:           500 to 3000 MHz

Amplitude:                      +16 dBm

E8241A
E8244A
E8251A
E8254A
E8247C
E8257C
E8257D
E8267C
E8267D
8663A
E8663B

 

Connections and Setup Procedures

All test equipment requires a 30 minute warm-up period to ensure accurate performance.

In the following test setup, direct cable and adapter connections are designated as solid lines. Changeable cable and adapter connections are designated as dashed lines.

 

  1. Connect all test equipment as shown.

  2. Connect GPIB cables to all GPIB-controlled test equipment.

  3. While performing this test, follow all instructions on the controller display.
     

Measuring Receiver Calibration Setup


AM Freq Response CW Frequency <= 1300 MHz Test Setup


AM Freq Response CW Frequency > 1300 MHz Test Setup