Giga-tronics 2508A, Руководство по эксплуатации

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Performance Verification
2500A Series Operation Manual, 34172 Revision C, March 2008
2. Set the Spectrum Analyzer to the following settings:
Reference Level +5 dBm
Span 5 kHz
Sweeptime 400 msec.
Resolution Bandwidth: < 100 Hz
Video Bandwidth:
> 30 kHz
3. Set the Function Generator for a 1 kHz Sine Wave output at 2.00 V peak-to-peak.
4. Connect the test equipment and UUT as shown in Figure 4-5, connecting the UUT directly to the RF
input of the Spectrum Analyzer. Connect the Function Generator output to the AM IN BNC.
NOTE: Measure the output of the Function Generator using a precision meter or oscilloscope to
ensure that its output is 2.00 Vp-p.
5. Set the Spectrum Analyzer to the test frequency. Center the signal using Peak Search and Marker to
Center Frequency functions.
6. Activate the Delta Marker function and press the Next Peak function or move the marker to the next
peak.
7. Measure and record the AM Depth in the appropriate column in Datasheet 6:
• If the first time through the test, record the AM Depth in the “30%” column.
• If the second time through the test, record the AM Depth in the “50%” column.
• If the third time through the test, record the AM Depth in the “90%” column.
Measure the difference in dB of one sideband and the carrier. Use the following formula to deter-
mine the AM depth in percentage:
AM% = 10^[(E
sb
- E
c
) /20]*200
Example: Carrier Peak is 0 dBm and one Sideband Peak is -10 dBm
AM% = 10^[(0 dBm -10 dBm)/20]*200
AM% = 10^(-0.5)*200
AM% = (.316)*200
AM% = 63.2
The measurement should be with a 10% range of the AM sensitivity setting.
8. Deactivate the AM function of the UUT and repeat Step 5 to Step 7 for the remaining test frequen-
cies in Datasheet 6, recording the AM depth for each in the appropriate column.
9. Set the AM Sensitivity of the UUT to 50% and repeat Step 7 to Step 8 for each of the test frequen-
cies in Datasheet 6, recording the AM depth for each measurement in the appropriate column.