Chapter 3 — Performance Verification 3-6 1 GHz Calibrator Frequency (ML248xx-Option 15, ML249xA)
ML248xx, ML249xA MM PN: 13000-00164 Rev. K 3-7
3-6 1 GHz Calibrator Frequency (ML248xx-Option 15, ML249xA)
The following procedure is used to measure the 1 GHz Calibrator output frequency of the ML248xA and
ML248xB power meters with option 15 and all ML249xA units.
Required Equipment
• Anritsu MF2412B Frequency Counter or equivalent
• RF Cable with N-type male connection at both ends
Procedure for 1 GHz Verification
1. Power on the power meter and frequency counter. Allow both to warm up for 15 minutes before taking
measurements.
2. On the MF2412B, press the Preset key.
3. On the MF2412B, press the Input key.
4. Ensure the Input CH is set to Input 1.
5. On the MF2412B, press the Return to Meas key.
6. Connect an RF cable from Input 1 of the MF2412B to the Calibrator Output of the power meter.
7. On the power meter, turn on the 1 GHz RF calibrator by pressing the Cal / Zero key, then the Calibrator
soft key. Ensure the 1GHz button is selected and press the RF Calibrator soft key.
8. Now the power meter calibrator output should be turned on and the MF2412B frequency counter should
be reading the frequency of the calibrator output. Record the frequency below and in Calibrator
Frequency Uncertainty of Appendix A:
F
meas
= ___________________ Hz
Calibrator Frequency Uncertainty
The sources of uncertainties of the frequency counter measurement at 1 GHz include:
• One Count: Least significant digits (LSD) of the frequency counter
• Time base accuracy from either of the following:
• GPS Disciplined Oscillator
• MF2412B Frequency Counter
• •Residual error of the frequency counter:
• Normal Mode; Measurement Frequency / 1E
10
• Fast Mode; Measurement Frequency / 2E
9
Use the following equation to determine the expanded measurement uncertainty (U
f
) with coverage factor
K = 2, 95 % level of confidence.
1. For the MF2412B, use the following numbers to determine U
f
.
• One count = 1
• Time base accuracy for the MF2412B:
• TBA = 7.5E
–8
with option 1
• TBA = 4.5E
–8
with option 2
• TBA = 1.5E
–8
with option 3